How much do screw chips, helices, and piston drills cost? | Prices depend on the build [OK Prostate Chip]

This page is based on entries from "ok-lab's diary" (https://ok-lab.hatenablog.com/), the Japanese development diary written by Mr. Okada, founder of OK Lab, a small company in Japan (Okada Comfortable Life Laboratory). Only the entries about "screw chip, helix, and piston drill prices" are summarized here, in order of publication. Past prices and sizes are as written at the time. Current prices come from the official product list (retrieved September 4, 2026). Quotations are translated from Japanese.

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Note: This page is a personal reading log by someone with no connection to the maker or the seller. It reflects the source entries as of their publication dates and makes no guarantee of accuracy or safety. The product is not a medical device; talk to a doctor about any health decision. Check the official site for current information. This page contains advertising.

In short

• Screw chip prices depend on material, construction, and separately charged parts.
• Mr. Okada changed processing fees and declined some designs because of manufacturing limits.
• Current listed screw add-ons cost ¥3,300 (about $21 at ¥156 = $1, rate as of 2026-09-04) or ¥3,500 (about $22 at ¥156 = $1, rate as of 2026-09-04) including tax, depending on the product.

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About this product

The OK Prostate Chip is a small device that is placed in the urethra (the urine passage) so that it acts on the prostate; the maker sells it in several shapes, sizes and materials. It is made and sold by OK Lab (Okada Comfortable Life Laboratory), a small company in Japan, through its own online store, and prices are in Japanese yen (JPY).

The maker's development diary, "ok-lab's diary", is written in Japanese. This page is an English summary of it, and every quotation is translated. OK Lab ships internationally, so readers outside Japan can order (see "Buying from outside Japan" below).

Product names on this page are plain-English descriptions. The official Japanese product name is shown once in the product table so you can find the same item in the store.

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Before you read: key terms

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What happens: screw chip, helix, and piston drill prices

The OK Prostate Chip is a small device placed in the urethra (urine passage) to act on the prostate. Screw chips (twisted solid chips) differ from helices (coiled wire structures). Screw add-ons attach to connecting lines, where the maker intends them to help hold the main chip's position. The piston drill combines a shaft, a sheath (outer sleeve), and a chip for movement within the urethra.

Screw chip prices fell when the original pricing rule ended

In an entry published in July 2018, Mr. Okada ended the original three-times-base-price rule. Revised prices were ¥5,000 (about $32 at ¥156 = $1, rate as of 2026-09-04) for glass and ¥4,000 (about $26 at ¥156 = $1, rate as of 2026-09-04) for resin, with a ¥2,000 (about $13 at ¥156 = $1, rate as of 2026-09-04) tax-excluded bending fee.

He attributed the revision to growing confidence in production and promised existing buyers credit against later orders. Resin work still limited capacity, and delivery could take considerably longer. Mr. Okada therefore directed these requests through custom orders.

(Source: ok-lab's diary, published July 2018)
https://ok-lab.hatenablog.com/entry/20180721/1532152353

Glass twist prices fell, while the short screw became custom-only

An entry published in August 2018 removed the short glass screw from the standard product list. Custom requests remained possible, with a ¥2,000 (about $13 at ¥156 = $1, rate as of 2026-09-04) screw-processing fee. No matching product can be confirmed on the current list.

Separately, glass twisting fell from ¥2,000 (about $13 at ¥156 = $1, rate as of 2026-09-04) to ¥1,000 (about $6 at ¥156 = $1, rate as of 2026-09-04), while resin twisting remained ¥2,000 (about $13 at ¥156 = $1, rate as of 2026-09-04) per chip. Mr. Okada attributed the glass reduction to more accurate production; resin work remained time-consuming. For products awaiting listing, he directed customers to request custom orders by email.

(Source: ok-lab's diary, published August 2018)
https://ok-lab.hatenablog.com/entry/20180825/1535182626

Screw add-on prices covered a separate part beside the main chip

The November 2019 entry introduced a multifunction screw add-on at ¥3,000 (about $19 at ¥156 = $1, rate as of 2026-09-04) excluding tax. Its standard dimensions were 15–18mm long and 8–9mm wide.

The diary placed it on the connecting thread and described a role in keeping the main chip in position. This version had a fixed position and could not be added afterward. Mr. Okada asked for it to be ordered together with the main product.

(Source: ok-lab's diary, published November 2019)
https://ok-lab.hatenablog.com/entry/2019/11/16/154802

Planned screw chip prices differed between resin and titanium

In July 2021, Mr. Okada published planned initial prices for newly manufactured screw chips. The resin screw was ¥3,000 (about $19 at ¥156 = $1, rate as of 2026-09-04), while the titanium screw was ¥7,000 (about $45 at ¥156 = $1, rate as of 2026-09-04), both excluding tax.

He explained that outsourced production required supplier pricing and a resale margin. The titanium screw was among the proposed products. No matching product can be confirmed on the current list.

(Source: ok-lab's diary, published July 2021)
https://ok-lab.hatenablog.com/entry/2021/07/10/125840

A successful resin twist request led to another priced design

In September 2023, a customer asked for a curved screw shape in white resin. Mr. Okada accepted without promising success because twisting and curving required different timing during manufacture.

The result encouraged him to develop a longer white-resin five-point twist, offered at ¥6,000 (about $38 at ¥156 = $1, rate as of 2026-09-04) excluding tax. The diary records successful shaping but no customer report about that new model's performance. No matching product can be confirmed on the current list.

(Source: ok-lab's diary, published September 2023)
https://ok-lab.hatenablog.com/entry/2023/09/16/122723

A smaller internal opening changed the sliding screw add-on design

In December 2023, Mr. Okada developed a screw for tube-covered thread (nylon thread inside silicone tubing). An initial 2.5mm opening allowed unwanted movement when wet.

He reported that a revised 2mm opening around 2.5mm tubing allowed adjustment while holding position more firmly. The add-on cost ¥3,000 (about $19 at ¥156 = $1, rate as of 2026-09-04) excluding tax, separately from the covered thread. Mr. Okada considered the screw-only arrangement sufficient for the add-on's usual role. No matching product can be confirmed on the current list.

(Source: ok-lab's diary, published December 2023)
https://ok-lab.hatenablog.com/entry/2023/12/02/122648

Mini screw prices reflected simpler work on the wire assembly

In November 2025, Mr. Okada priced mini screws on looped shape-memory wire (springy connecting wire) at ¥1,000 (about $6 at ¥156 = $1, rate as of 2026-09-04) each excluding tax. They were approximately 10mm long and 7–8mm wide; larger screws cost ¥2,000 (about $13 at ¥156 = $1, rate as of 2026-09-04) each excluding tax.

He attributed the lower charge to easier attachment to wire than to flexible nylon thread. No matching product can be confirmed on the current list. For the add-on nearest the main chip, Mr. Okada suggested the ordinary larger size for its conventional role.

(Source: ok-lab's diary, published November 2025)
https://ok-lab.hatenablog.com/entry/2025/11/01/122937

Reversible piston drill prices excluded the extra chip itself

The May 2026 entry described a reversible piston drill with a chip at each end of its sheath. The additional connection cost ¥2,000 (about $13 at ¥156 = $1, rate as of 2026-09-04) excluding tax, above the single-ended assembly's price.

That charge covered connecting the opposite chip and shaft; the second chip's own price remained separate. No matching product can be confirmed on the current list.

(Source: ok-lab's diary, published May 2026)
https://ok-lab.hatenablog.com/entry/2026/05/02/122917

Micro helix prices separated the shaft from each coiled pair

In June 2026, Mr. Okada introduced a fine-wire double helix using 0.04mm or 0.05mm wire. The shaft cost ¥3,000 (about $19 at ¥156 = $1, rate as of 2026-09-04) up to 25cm or ¥4,000 (about $26 at ¥156 = $1, rate as of 2026-09-04) up to 35cm, excluding tax.

Each paired helix section within a 20mm interval cost ¥1,500 (about $10 at ¥156 = $1, rate as of 2026-09-04) excluding tax. Mr. Okada said detailed comparisons of how the new design felt were not yet completed. No matching product can be confirmed on the current list.

(Source: ok-lab's diary, published June 2026)
https://ok-lab.hatenablog.com/entry/2026/06/27/122906

Smaller helix prices distinguished the prostate component from an additional section

The July 2026 entry introduced a shorter helix approximately 40–45mm long, using 0.1mm wire with a 10–13mm width. The prostate section alone cost ¥4,500 (about $29 at ¥156 = $1, rate as of 2026-09-04) excluding tax.

A version also containing a helix for the lower urethral section cost ¥9,000 (about $58 at ¥156 = $1, rate as of 2026-09-04) excluding tax. Thread added ¥1,000 (about $6 at ¥156 = $1, rate as of 2026-09-04) excluding tax to either configuration, and other accessories remained separate. No matching product can be confirmed on the current list.

(Source: ok-lab's diary, published July 2026)
https://ok-lab.hatenablog.com/entry/2026/07/18/122919

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The maker's answer to screw chip, helix, and piston drill prices

Mr. Okada's replies make construction limits part of the buying decision, alongside price.

Motorized resin twist problems persisted despite successful shaping and working motors

In February 2019, a customer wanted a twisted resin chip with motors at both ends. Mr. Okada initially declined, then tried making it.

Waterproof testing revealed leakage, so he reinforced the build; both motors were working when he wrote the entry. He suspected stress on the embedded wiring and possible performance deterioration. No matching product can be confirmed on the current list. Mr. Okada therefore did not recommend the motorized resin twist.

(Source: ok-lab's diary, published February 2019)
https://ok-lab.hatenablog.com/entry/2019/02/23/142754

The new resin screw add-on kept its price but changed compatibility

In August 2021, the diary announced an upcoming resin screw add-on launch at ¥3,000 (about $19 at ¥156 = $1, rate as of 2026-09-04) excluding tax. This model required two threads.

Mr. Okada described it as reusable when the threads were replaced, unlike the older resin version with embedded threads. That was a difference in construction, with the same published accessory price. For customers choosing two threads, Mr. Okada favored this model over the older embedded-thread version.

(Source: ok-lab's diary, published August 2021)
https://ok-lab.hatenablog.com/entry/2021/08/28/125823

Sliding screw add-ons required tubing over their wire connections

In April 2024, Mr. Okada described screw add-ons for shape-memory wire (springy wire connecting device parts). He reported a smallest screw size of about 7.5mm and an additional price of ¥3,000 (about $19 at ¥156 = $1, rate as of 2026-09-04) excluding tax.

A sliding version required a tube cover; without that cover, only a fixed-position screw was possible. The covering itself was a separately priced component. Mr. Okada advised stopping use if the outer resin at a connection broke.

(Source: ok-lab's diary, published April 2024)
https://ok-lab.hatenablog.com/entry/2024/04/13/123053

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How screw chip, helix, and piston drill prices changed over time

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OK Prostate Chip products related to screw chip, helix, and piston drill prices

The current list confirms the following individual products at tax-inclusive prices.

Products that appear in these entries

(Source: ok-lab's diary, published December 2019)
https://ok-lab.hatenablog.com/entry/2019/12/28/131319

(Source: ok-lab's diary, published December 2024)
https://ok-lab.hatenablog.com/entry/2024/12/21/122903

(Source: ok-lab's diary, published November 2025)
https://ok-lab.hatenablog.com/entry/2025/11/08/122932

Products the diary mentioned as alternatives

(Source: ok-lab's diary, published August 2021)
https://ok-lab.hatenablog.com/entry/2021/08/28/125823

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Common worries about screw chip, helix, and piston drill prices

Customers asked about compatibility, custom dimensions, and whether to wait before buying.

"Can screw add-ons fit a motorized chip's cable?"

In December 2019, a customer asked for a screw add-on on a motorized chip (a chip with a vibration motor). Mr. Okada investigated, changed the construction after strength concerns, and adopted it after about three days of testing.

The minimum gap became 2mm, and the price was ¥3,000 (about $19 at ¥156 = $1, rate as of 2026-09-04) excluding tax. The diary does not record the customer's later experience with it. Mr. Okada specified ordering it with the motorized chip because later fitting was unavailable.

(Source: ok-lab's diary, published December 2019)
https://ok-lab.hatenablog.com/entry/2019/12/21/150646

"Should I wait before paying for screw add-ons?"

In November 2024, a customer requested a quote for a covered-wire assembly with sliding screws. Staff quoted ¥9,900 (about $63 at ¥156 = $1, rate as of 2026-09-04) for three screws and mentioned a forthcoming design.

The customer decided to wait and compare before ordering. Mr. Okada also advised waiting if the unreleased design was of interest. That advice concerned the forthcoming product discussed in that entry.

(Source: ok-lab's diary, published November 2024)
https://ok-lab.hatenablog.com/entry/2024/11/02/122858

"Can a screw add-on fit curved wire?"

In December 2024, a customer wanted a screw between the prostate chip and the lower support chip. Mr. Okada replied that the screw's internal passage could only be straight, so it could not occupy the wire's curved section. The diary does not record whether the order was completed.

(Source: ok-lab's diary, published December 2024)
https://ok-lab.hatenablog.com/entry/2024/12/21/122903

"Can a longer screw charm fit the quoted build?"

In April 2026, a customer requested 20mm screw charms on a loop-based device. Mr. Okada said the curved location limited a straight screw's length.

He tentatively proposed approximately 15mm long and 10mm wide, with two charms quoted at ¥3,300 (about $21 at ¥156 = $1, rate as of 2026-09-04) each. The customer then changed the requested gap between loops to 10mm; completed delivery is not recorded. Mr. Okada's proposal remained conditional on what could fit the curve.

(Source: ok-lab's diary, published April 2026)
https://ok-lab.hatenablog.com/entry/2026/04/18/122906

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Buying from outside Japan

OK Lab ships internationally to countries covered by Japan Post's EMS courier service. Overseas orders are paid in advance by PayPal.

Each order carries a ¥400 (about $3 at ¥156 = $1, rate as of 2026-09-04) handling fee, and EMS shipping is charged on top. These terms come from OK Lab's official sales-terms page (written here as plain text, not a link: ok-lab.net/docs/law), checked on September 7, 2026; confirm them on the official store before you order, because they can change.

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Summary of this article

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Source: ok-lab's diary (Okada Comfortable Life Laboratory). The original entries are in Japanese; quotations on this page are translated. Photos and videos are on the original entries.