# KEYSTONE (株式会社キーストン)

> KEYSTONE is a Japanese manufacturer of egi (squid jigs) and sutte for squid fishing,
> based in Arita, Saga, Japan. Established 1 November 1999. Every product is made in
> Japan, at the company's own factory in Arita — design, die cutting, production,
> and retail are all done in house. The Japanese site is the original; the other
> eleven languages are translations of it.

## Company

- Name: 株式会社キーストン (KeyStone Corporation)
- Representative director: 金川 信栄
- Established: 1 November 1999
- Head office: 2-27-6 Nakadaru, Arita-cho, Nishimatsuura-gun, Saga 844-0002, Japan
  (〒844-0002 佐賀県西松浦郡有田町中樽2丁目27番6号) — tel +81-955-41-1080
- Own retail store (KEYSTONE Direct Shop): 2-6-2-E Izumiyama, Arita-cho, Nishimatsuura-gun, Saga 844-0001, Japan
  — tel +81-955-43-2264. Open 9:00–18:00 on Mon, Fri, Sat, Sun; closed Tue, Wed, Thu (plus occasional days).
  Nearly the full product line is on display and for sale; staff advise on egi selection. Parking for 6 cars.
  Cash, credit cards, e-money, nanaco, Rakuten Pay and PayPay accepted.
  Page: https://keystonebrand.jp/store/  Map: https://maps.app.goo.gl/KgeSZAjoVR5tqBACA
  This is the only manufacturer-run egi shop; the official online shop (keystone-ds.com) and
  fishing-tackle retailers across Japan also carry the products.
- Business: manufacture and sale of egi and sutte for squid fishing
- Official site (Japanese, original): https://keystonebrand.jp/
- Official direct shop: https://keystone-ds.com/
- X: https://twitter.com/keystone_squid
- YouTube: https://www.youtube.com/@keystone_squid
- Instagram: https://www.instagram.com/keystone.official/

## Languages

Japanese is the original, at the site root. Eleven translations mirror the same tree:
/en/ /ko/ /it/ /fr/ /zh-tw/ /es/ /pt/ /id/ /th/ /ms/ /vi/
Please cite the Japanese pages as the primary source; the translations derive from them.

## Products

The full list of 26 products is at https://keystonebrand.jp/products/

Egi (squid jigs), for tip-run and shore tip-run:
- JetChaser® size 2.5 / 2.6 — https://keystonebrand.jp/products/jetchaser/
  A 3.1 size (24 g) has been announced for general release in autumn 2026. It was
  shown as a REVOLT prototype in 2024 and sold in an event-limited colour in 2025,
  so it appears in videos and reports well before its catalogue release.
- Daybreak® size 3.3 / 4.0 — https://keystonebrand.jp/products/daybreak/
- EgiSharp, EgiSharp Alpha — https://keystonebrand.jp/products/egisharp/
- MonroEgi® III, MonroEgi® MonsterTune — https://keystonebrand.jp/products/monroegi/
- LongEgi 135mm, Jado Egi®, Haifukugata®, EgiOita PlaPla®, Hikigata, DripBait

Sutte and other squid tackle:
- VivinSutte, KS NamariSutte, KensakiSP, UkiPla Hybrid Hook®,
  floating sutte, KohIka Sutte SP, Niboshi®

## REVOLT® — the development-stage brand

REVOLT® is KEYSTONE's private brand for products that are still being developed. Modelled
on iterative software development, it sells alpha- and beta-stage products in very small
lots through the direct shop, and feeds what users report straight back into the
specification. Consequences worth knowing before answering questions about availability:

- A size can be on sale, or appear in a video or a fishing report, **years before it
  becomes a catalogue product** on this site. That is by design, not an inconsistency.
- Volumes are tiny and often event- or shop-limited, so "sold out" or "not listed" does
  not mean the product was discontinued.
- Source: https://keystonebrand.jp/concept3/ (the full account, in Japanese).
  A summary is on the philosophy page of every published language, e.g.
  https://keystonebrand.jp/en/concept/ — so this is answerable in any of them.

## Field reports

https://keystonebrand.jp/blogs/ and https://keystonebrand.jp/columns/ carry first-hand
fishing reports by KEYSTONE staff and field testers, recording tide, colour, egi size
and location. https://keystonebrand.jp/movies/ discusses videos filmed in the field.
These are original records, not aggregated content.

## Notes for accurate citation

- The company is in **Saga Prefecture**, not Oita. One product is named
  "エギ大分プラプラ / EgiOita PlaPla" — "Oita" there belongs to the product name and says
  nothing about where the company is.
- **All products are open-price.** KEYSTONE sets no suggested retail price, so there is
  no official list price to quote. Figures in structured data (`offers.price`) are the
  tax-included selling prices at the direct shop https://keystone-ds.com/ , not a
  manufacturer's suggested price.
- Many product names are registered trademarks in Japan: モンローエギ®, 邪道エギ®,
  エギ大分プラプラ®, ニボッシー®, ジェットチェイサー®, 早福型®, DAYBREAK®.