How does a rectal prostate chip work? | Shape matters, and removal problems were reported [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 "rectal chip use" 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

• The diary reports varied sensations and removal difficulties with rectal chips.
• Mr. Okada discouraged automatic size increases and withheld designs he considered risky.
• The current list includes resin and ceramic rectal chips; several later designs have no confirmed match.

If you see blood in your urine, even a small amount or for the first time, do not wait and see. See a urologist right away.

If you suddenly cannot urinate, or the device cannot be removed, do not try to fix it yourself. Go to a medical facility, including emergency care, immediately.

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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: rectal prostate chip use

The OK Prostate Chip is a device placed in the urethra, the urine passage, for intended prostate stimulation. The rectal chips discussed here are different designs placed in the rectum (the bowel area reached through the anus). Mr. Okada describes them as devices for prostate stimulation, with some versions also intended as bowel aids. The diary covers rigid shapes, suspended designs, and flexible loops, including reports of removal difficulties.

The spiral rectal chip came with a warning about expulsion

In an entry published in October 2018, the spiral chip (a coiled strip) cost ¥8,000, (about $51 at ¥156 = $1, rate as of 2026-09-04) tax excluded. It measured 11cm overall, with 8cm inside the bowel and a maximum width of 35mm.

Mr. Okada also described a version of use involving a water-filled condom around the chip. He warned that straining could expel the covering. He therefore recommended a support accessory or tight support underwear.

(Source: ok-lab's diary, published October 2018)
https://ok-lab.hatenablog.com/entry/20181031/1540960147

A customer reported that forced rectal chip removal felt dangerous

An entry published in November 2018 records a customer's 3-hour trial of a two-bump U-turn chip (a strip curved back on itself). The customer described sustained sensation but felt the hooked shape made forceful removal dangerous.

Removal was completed without reported abnormalities, and the customer reported no deformation of the chip. Mr. Okada thanked the customer and acknowledged that established devices could outperform his designs in some respects. He asked for further problem reports and cautioned against excessive expectations.

(Source: ok-lab's diary, published November 2018)
https://ok-lab.hatenablog.com/entry/20181117/1542436271

Removal difficulties put the narrowed-loop rectal chip launch on hold

In an entry published in December 2018, Mr. Okada described trouble removing a 6cm-wide narrowed-loop prototype during his own test. He wrote that a direct pull did not release it and that the difficulty briefly alarmed him. He eventually removed it, but put the launch on hold because he did not want customers to experience similar anxiety.

No matching product can be confirmed on the current list. Mr. Okada advised understanding a chip's shape, even when another design had seemed straightforward in his tests.

(Source: ok-lab's diary, published December 2018)
https://ok-lab.hatenablog.com/entry/20181201/1543652709

Ceramic rectal chip prices differed by shape in December 2019

In an entry published in December 2019, Mr. Okada introduced ceramic rectal chips and reported that they felt lighter than glass examples. The single-bump U-turn model was ¥5,000 (about $32 at ¥156 = $1, rate as of 2026-09-04), and the two-bump model was ¥6,000 (about $38 at ¥156 = $1, rate as of 2026-09-04), both tax excluded.

The free-design ceramic models were ¥5,000, (about $32 at ¥156 = $1, rate as of 2026-09-04) tax excluded. No matching product can be confirmed on the current list. Mr. Okada said ceramic custom work required an individual quotation because making a separate mold added expense.

(Source: ok-lab's diary, published December 2019)
https://ok-lab.hatenablog.com/entry/2019/12/07/162608

The suspended rectal chip introduced silicone coating and bowel-movement claims

In an entry published in September 2022, Mr. Okada introduced an aluminum chip fully covered in silicone (a coating intended to resist scratches and soiling). He claimed it could remain in place during some bowel movements, although firmer stool could expel it.

He also described cleaning with a bidet toilet (a toilet with a washing spray) as part of the design's intended convenience. No matching product can be confirmed on the current list. Mr. Okada favored silicone suspension tubing over the fabric control belt for cleanliness.

(Source: ok-lab's diary, published September 2022)
https://ok-lab.hatenablog.com/entry/2022/09/10/122847

Flexible rectal chip alternatives introduced separate single-loop and double-loop prices

In an entry published in July 2025, Mr. Okada introduced large flexible loop devices (wire-and-tube designs without solid chip bodies). His standard double-loop version was ¥9,000, (about $58 at ¥156 = $1, rate as of 2026-09-04) tax excluded, while a single-loop version was ¥5,000, (about $32 at ¥156 = $1, rate as of 2026-09-04) tax excluded.

He reported that the external loop adapted to sitting without getting in his way. No matching product can be confirmed on the current list. Mr. Okada suggested a single loop for a milder option, while acknowledging that he had not tested that version.

(Source: ok-lab's diary, published July 2025)
https://ok-lab.hatenablog.com/entry/2025/07/19/122907

A longer rectal chip prototype failed to produce fluid release

In an entry published in August 2025, Mr. Okada tested a flexible prototype measuring about 25cm overall. It targeted the seminal vesicles (a separate stimulation target associated with fluid in the diary).

He reported that it did not produce the intended fluid release, attributing this to insufficient mass despite the device's size and springiness. He described the result as mild massage only. No matching product can be confirmed on the current list. Mr. Okada offered custom sizing of the additional loop.

(Source: ok-lab's diary, published August 2025)
https://ok-lab.hatenablog.com/entry/2025/08/02/123058

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The maker's answer to rectal prostate chip use

Mr. Okada's replies raised concerns about lubricant compatibility, covering movement, and pressure on newly made resin.

The maker's rectal chip lubrication warning contradicted his personal choice

In an entry published in November 2018, Mr. Okada acknowledged using petroleum jelly while explaining that oil-based lubrication was officially unsuitable with condoms. He attributed that restriction to oil damaging the rubber.

His personal practice therefore differed from the restriction he reported. Mr. Okada pointed to lubricant sold by condom manufacturers as the more reassuring choice.

(Source: ok-lab's diary, published November 2018)
https://ok-lab.hatenablog.com/entry/20181110/1541826499

A rectal chip covering problem remained despite the control belt

An entry published in November 2018 describes a customer's trial involving a control belt (an elastic pressure-control accessory) and a covered spiral chip. The customer reported rubbing pain after 5 hours and the whole chip moving inside at around 12 hours.

The customer reported completing removal without bleeding or other abnormalities. Mr. Okada attributed the inward movement to the covering's fastening position. His reply advised reconsidering that arrangement.

(Source: ok-lab's diary, published November 2018)
https://ok-lab.hatenablog.com/entry/20181123/1542963370

Strong wand pressure deformed a newly made resin rectal chip

In an entry published in December 2018, Mr. Okada tested a rectal chip with an attachment for a handheld vibrating wand. The chip had been made only 1 day earlier, and he reported substantial resin deformation under strong pressure.

The attachment option was priced at ¥1,000 (about $6 at ¥156 = $1, rate as of 2026-09-04) extra, tax excluded, as published that month. No matching product can be confirmed on the current list. Mr. Okada cautioned against strong pressure during the first 2 months after purchase.

(Source: ok-lab's diary, published December 2018)
https://ok-lab.hatenablog.com/entry/20181222/1545459719

If you see blood in your urine, even a small amount or for the first time, do not wait and see. See a urologist right away.

If you suddenly cannot urinate, or the device cannot be removed, do not try to fix it yourself. Go to a medical facility, including emergency care, immediately.

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How rectal prostate chip use changed over time

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OK Prostate Chip products related to rectal prostate chip use

The current list confirms several resin and ceramic products discussed in these entries, including designs involved in reported problems.

Products that appear in these entries

(Source: ok-lab's diary, published October 2018)
https://ok-lab.hatenablog.com/entry/20181031/1540960147

(Source: ok-lab's diary, published November 2018)
https://ok-lab.hatenablog.com/entry/20181117/1542436271

(Source: ok-lab's diary, published November 2018)
https://ok-lab.hatenablog.com/entry/20181123/1542963370

(Source: ok-lab's diary, published December 2019)
https://ok-lab.hatenablog.com/entry/2019/12/07/162608

Products the diary mentioned as alternatives

(Source: ok-lab's diary, published December 2018)
https://ok-lab.hatenablog.com/entry/20181222/1545459719

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Common worries about rectal prostate chip use

The recorded questions concern absent sensation, catching during removal, and whether a different shape would reach farther.

"Does absent rectal chip sensation mean a larger size is needed?"

An entry published in November 2018 records a customer who felt nothing and asked whether a larger chip would help. Mr. Okada said sensation could vary with physical condition and bowel contents. His explanation also discussed wear duration and the chip's position, depth, and angle.

He mentioned a dedicated seminal-vesicle design but said he was withholding sales because he considered it dangerous. The entry does not record a successful response from this customer. Mr. Okada advised against increasing size while the existing chip produced no sensation.

(Source: ok-lab's diary, published November 2018)
https://ok-lab.hatenablog.com/entry/20181117/1542436271

"Could a pointed rectal chip catch during removal?"

In an entry published in November 2018, Mr. Okada addressed a customer's concern about a projecting tip catching the bowel wall. He described a rounded, closed-loop revision intended to remove that exposed tip.

He reported that his own test went as expected; the paragraph does not record the requesting customer's later experience. Mr. Okada directed requests outside the published specifications to custom ordering.

(Source: ok-lab's diary, published November 2018)
https://ok-lab.hatenablog.com/entry/20181123/1542963370

"Would the newer rectal chip reach farther?"

In an entry published in December 2018, the November customer reported continued lack of pleasure and asked whether the newer design reached farther. Mr. Okada initially said he needed time to consider a proposal. His eventual response offered a special prototype measuring 12cm long and 6cm wide.

No matching product can be confirmed on the current list. The diary does not record whether the customer ordered it or how it felt in use. Mr. Okada invited a custom request if that proposal appealed to the customer.

(Source: ok-lab's diary, published December 2018)
https://ok-lab.hatenablog.com/entry/20181201/1543652709

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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.