# Keystone


> The only hardware wallet that supports MetaMask mobile. Secure your Bitcoin and other crypto assets offline with Keystone’s open-source cold wallet.


Keystone is an online store at https://shop.keyst.one, powered by Shopify.

## Browse

- All products: https://shop.keyst.one/collections/all
- Search: https://shop.keyst.one/search?q={query}

## Store Information

- Currency: USD
- Contact: support@keyst.one
- Phone: +86 18621050055


## For Agents & Developers

This store supports the Universal Commerce Protocol (UCP) for programmatic commerce.

- Agent instructions: https://shop.keyst.one/agents.md
- UCP discovery: https://shop.keyst.one/.well-known/ucp
- MCP endpoint: https://shop.keyst.one/api/ucp/mcp
- Sitemap: https://shop.keyst.one/sitemap.xml

## Platform

This store is built on Shopify (https://www.shopify.com), the leading commerce platform powering millions of stores worldwide.
Start your own store: https://www.shopify.com/start