Large or small prostate chip? | Bigger does not always feel better [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 "large versus small prostate chips" 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

Larger chips sometimes felt easier to locate, but reports also describe bleeding, harder removal, and greater strain.

The maker distinguished initial entry, handling, staying in place, and sensation when discussing size.

Current listings include several models discussed here, but do not confirm their historical size options.

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: large versus small prostate chips

The OK Prostate Chip is a small device placed in the urethra to act on the prostate. The comparisons below concern the length, width, thickness, and shape of that device inside the urine passage. Customers and Mr. Okada describe differences in locating the chip, pressure, and retention (staying in position). Their reports also distinguish the initial sensation from what they felt after the chip had remained in place.

A larger prostate chip was easier to locate but caused bleeding

In an entry published in January 2018, a customer reviewed a custom short chip extended by about 1cm. They found it much easier to handle and locate than the standard short version. They reported little difference in prostate stimulation, however.

After approximately 12 hours, they reported slight bleeding and considered prolonged use difficult. Mr. Okada acknowledged the report and discussed friction as a concern. He advised treating the account as one person's experience because responses vary substantially.

(Source: ok-lab's diary, published January 2018)
https://ok-lab.hatenablog.com/entry/20180118/1516263011

Cracking in larger linked prostate chips prompted the maker to suspend sales

A January 2020 entry recorded a customer's questions about lengths for a linked ceramic design (Rei). Staff initially supplied estimates for different combinations. The reply was then overtaken by a separate report of a cracked connection.

Mr. Okada suspected that a long design placed excessive force on the joint. His revised response was to suspend sales of the linked design for the time being.

(Source: ok-lab's diary, published January 2020)
https://ok-lab.hatenablog.com/entry/2020/01/11/151714

A larger bumpy prostate chip brought handling benefits alongside reported bleeding

An October 2020 entry compared a customer's long, thick bumpy 3-1 chip with their smaller medium-length SS chip. They found the larger model easier to locate, but reported rotation during insertion followed by fresh bleeding. They also described more difficult removal.

Mr. Okada thanked them for the account. The diary does not record a medical assessment or later recovery from that bleeding.

(Source: ok-lab's diary, published October 2020)
https://ok-lab.hatenablog.com/entry/2020/10/24/115457

A smaller prostate chip meant one component instead of linked twins

In a July 2021 entry, Mr. Okada introduced a blue resin component from a twin design. His account of excessive burden concerned the connected titanium twin he had previously used. He said that configuration prevented prolonged use.

He reported no problems during about 3 days with the single component. This was his personal comparison across both configuration and material.

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

A tiny prostate chip was described as gentle but came out readily

In a September 2021 entry, Mr. Okada described an introductory blue chip measuring 15mm long. He said it fitted wholly within the prostate region without burdening the surrounding sphincters (muscles controlling the urine passage). He also reported that ordinary urination could expel it immediately.

He repositioned the product as introductory after finding its earlier handling concept unreliable. The entry therefore records both a claimed comfort benefit and a retention problem.

(Source: ok-lab's diary, published September 2021)
https://ok-lab.hatenablog.com/entry/2021/09/04/125843

Larger prostate chips felt less burdensome in one customer's comparison

A January 2022 entry reported a customer's better fit with an extended blue resin chip, size L, measuring 12mm wide. They reported no pain over 4 days, compared with a 2-day limit with their smaller chips. Those earlier models were a short twisted ceramic chip and a medium-length blue resin chip.

Mr. Okada suggested that wider spacing between the larger model's bumps reduced pressure on the sphincter. He acknowledged that the smaller models feeling more burdensome had surprised him.

(Source: ok-lab's diary, published January 2022)
https://ok-lab.hatenablog.com/entry/2022/01/15/124252

Small prostate chips could still feel strong, Mr. Okada suggested

In a May 2024 entry, Mr. Okada described an S-shaped multi-part chip (Prostate Alien). Its 4 width options were SS at 7mm, S at 8mm, M at 9mm, and L at 10mm. The standard assembly cost ¥13,000 (about $83 at ¥156 = $1, rate as of 2026-09-04) excluding tax, as published that month.

He believed the narrowest version could still provide strong sensation and resist coming out because of its shape. He suggested considering a narrower size than a customer's usual chip.

(Source: ok-lab's diary, published May 2024)
https://ok-lab.hatenablog.com/entry/2024/05/18/122913

A smaller movable prostate chip felt milder but stayed less firmly

A March 2026 entry shared a customer's comparison of movable ceramic chips: short SS and medium-length S. They had worried that the short model's raised rubber section might cause friction, but reported easier handling instead. They described milder stimulation and less burden, suggesting it suited longer use.

However, it came out more readily during urination and ejaculation. Mr. Okada welcomed the report that the rubber had not caused the anticipated problem.

(Source: ok-lab's diary, published March 2026)
https://ok-lab.hatenablog.com/entry/2026/03/14/122910

Smaller spiral prostate chips followed the maker's reported heart-failure episode

In a July 2026 entry, Mr. Okada reported what he described as heart failure after brief use of a larger angular spiral prototype. He associated this with strong pressure, while reporting no problems during longer use of a smaller prototype. These statements describe his experience and interpretation.

The smaller prostate section measured 40-45mm long and 10-13mm wide. Published prices were ¥4,500 (about $29 at ¥156 = $1, rate as of 2026-09-04) for that section or ¥9,000 (about $58 at ¥156 = $1, rate as of 2026-09-04) for a two-section assembly, excluding tax. The same entry listed an additional ¥1,000 (about $6 at ¥156 = $1, rate as of 2026-09-04) excluding tax for the thread.

(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 large versus small prostate chips

The maker's suggestions depended on the design, the customer's experience, and the problem being discussed.

A smaller screw prostate chip was suggested for existing short-chip users

In a July 2018 entry, Mr. Okada discussed a screw-shaped chip 24mm long. He said its whole length could fit within the prostate region. His suggested audience was customers who already noticed effects with ordinary short chips.

He recommended considering the smaller screw design for those customers. He also favored a stopper accessory as a precaution.

(Source: ok-lab's diary, published July 2018)
https://ok-lab.hatenablog.com/entry/20180714/1531551648

Smaller prostate chips were suggested after discomfort disturbed one customer's sleep

In an August 2019 entry, a customer asked about continuous use after a ceramic chip's presence disturbed a nap. Mr. Okada suggested that shape or excessive size might explain the discomfort. His tentative distinction favored larger chips for brief use and smaller chips for longer periods.

The diary does not record whether a smaller purchase resolved the problem. His response offered that size distinction rather than a recorded maximum duration.

(Source: ok-lab's diary, published August 2019)
https://ok-lab.hatenablog.com/entry/2019/08/24/125858

A small prostate chip was the staff's suggested first purchase

A June 2020 entry shared questions about risks, size, and difficulty from a Korean customer outside Japan. Staff distinguished easier initial entry with smaller chips from easier handling with somewhat larger ones. They also said some customers experienced no sensation.

The diary does not record whether this customer ordered a device. Staff suggested a small, inexpensive single chip as a first purchase for someone without prior urethral experience.

(Source: ok-lab's diary, published June 2020)
https://ok-lab.hatenablog.com/entry/2020/06/27/120614

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 large versus small prostate chips changed over time

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OK Prostate Chip products related to large versus small prostate chips

The current list includes models from the comparisons and an accessory suggested for outward movement.

Products that appear in these entries

(Source: ok-lab's diary, published January 2022)
https://ok-lab.hatenablog.com/entry/2022/01/15/124252

Products the diary mentioned as alternatives

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

The custom extended short chip, linked ceramic design, bumpy 3-1 chip, single twin component, and introductory blue chip are historical items. No matching product can be confirmed on the current list.

Other unmatched items include the multi-part S-shaped design, movable ceramic chips, and the historical screw, connected, and spiral prototypes. No matching product can be confirmed on the current list.

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Common worries about large versus small prostate chips

The reader questions distinguish urinary symptoms, staying in place, and the strength of sensation.

"Can a bigger prostate chip make me urinate more often?"

An October 2019 entry recorded a customer's question about urinating more frequently with a chip present. Mr. Okada thought poor fit or a sphincter gripping a large chip could increase that likelihood. He also raised another possible cause involving inflammation. The diary does not record a confirmed explanation for this customer's symptoms.

(Source: ok-lab's diary, published October 2019)
https://ok-lab.hatenablog.com/entry/2019/10/12/125944

"Does a bigger prostate chip stay in place better?"

A February 2020 entry discussed a customer's size question after a curved medium-length chip moved farther inward and caused urgency. Mr. Okada said increasing size improved retention. He also stressed that larger chips could be harder to remove. The diary does not record the customer's experience after any size change.

(Source: ok-lab's diary, published February 2020)
https://ok-lab.hatenablog.com/entry/2020/02/01/151232

"Does a small prostate chip mean weaker sensation?"

A January 2022 entry described a customer in Switzerland expecting a hot sensation previously experienced with another urethral device. Their chips felt pleasant after a while, but did not produce that heat. Mr. Okada explained that a chip smaller than the surrounding passage produced less pressure.

He said increasing size could intensify heat, while separating that sensation from enjoyment. His advice also emphasized the person's mood and receptiveness.

(Source: ok-lab's diary, published January 2022)
https://ok-lab.hatenablog.com/entry/2022/01/08/123729

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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.