# Keystone > Secure Cold Wallet for Effortless Transactions Keystone is a hardware wallet provider offering air-gapped devices for self-custody of digital assets. It serves cryptocurrency holders seeking offline key storage compatible with a range of software wallets. Keystone is a hardware wallet company that designs air-gapped devices for self-custody of digital assets. Its wallets keep private keys isolated from internet-connected devices, using secure elements for key generation and storage and QR codes or offline transfer methods to sign transactions without a direct network or cable connection. The products target individuals and developers who want direct control over their private keys rather than relying on centralized custodians. The approach addresses a common weak point in digital asset security, the exposure of private keys to networked devices during transaction signing. By keeping signing operations physically isolated and verifiable through open source firmware, the wallets aim to reduce the attack surface associated with connected hardware. The devices are designed for interoperability with numerous third-party software wallets and blockchain applications, letting users choose their preferred interface while keeping key material offline. The flagship Keystone 3 Pro hardware wallet anchors a broader lineup that includes seed phrase storage tablets, developer hardware, and protective accessories. Keystone also maintains firmware, a companion application, and documentation supporting device setup and asset management across a wide range of supported networks. Its products are used by individual holders, long-term custodians of digital assets, and developers building on top of its open source firmware. - Type: Company - Sector: Custody and Wallets - Status: Active - Founded: 2018-01-01 - Profile: https://thegrid.id/profiles/Keystone ## Products - [Keystone 3 Pro](https://thegrid.id/profiles/Keystone): Keystone 3 Pro is an air-gapped hardware wallet that stores private keys offline for managing cryptocurrency across multiple blockchains. It uses three independent secure element chips alongside QR code and micro SD card based data transfer instead of USB or Bluetooth, removing network-connected attack surfaces during transaction signing. The device supports multiple seed phrases, Shamir backup, and pairs with numerous third-party software wallets, letting individual holders and self-custody users sign transactions while keys remain isolated from internet-connected devices. (Hardware Wallet, Live, Main Product) - [Keystone Tablet](https://thegrid.id/profiles/Keystone): Keystone Tablet is a physical seed phrase backup device made from stainless steel letter tiles for storing cryptocurrency recovery phrases. It uses an industrial etching process to permanently mark seed words onto metal, providing resistance to fire, water, and corrosion compared with paper backups. Self-custody wallet users rely on it to preserve access to funds if a primary device or paper backup is lost or destroyed, with variants offering individual letter slots or a punch based alternative for added durability. (Service Provider, Live) - [Keystone Nexus](https://thegrid.id/profiles/Keystone): Keystone Nexus is a self-custody software wallet application that pairs with Keystone hardware wallets to manage crypto assets. It lets users send, receive, and swap multiple cryptocurrencies and tokens from a mobile interface while transaction signing remains isolated on the paired hardware device. The app serves individual holders seeking a companion interface to their air-gapped hardware wallet for daily portfolio management. (Wallet, Live) - [ForgeBox](https://thegrid.id/profiles/Keystone): ForgeBox is an open-source hardware development kit that provides a secure hardware foundation for developers to build and deploy their own custom code. It is built with multiple secure element chips and a self-destruct mechanism, allowing developers to establish their own root of trust so that only code signed by their private key can execute on the device. The product targets Web3 developers building custom security applications rather than end users seeking a ready-to-use wallet. (Developer Tooling, Live) ## Links - [Main](https://keyst.one) - [Blog](https://blog.keyst.one) - [Documentation](https://guide.keyst.one/docs/category/keystone-3-pro) - [Media Kit/branding](https://drive.google.com/drive/folders/1MqffY73AbWE3ItSE6s_YP8SD7k1Gbz8r) - [Privacy policy](https://keyst.one/privacy-policy) - [Terms of Service](https://keyst.one/keystone-terms-of-use) - [Farcaster](https://warpcast.com/keystonewallet) - [Reddit](https://www.reddit.com/r/KeystoneWallet) - [Telegram](https://t.me/KeystoneWallet) - [Twitter / X](https://x.com/KeystoneWallet) - [YouTube](https://www.youtube.com/channel/UCaReIdawwYPPcyWGoNunF7g) ## Legal This data is provided under two licensing models. Model 1 - open data. The open data core is licensed under the Open Database License (ODbL) — a copyleft/share-alike license allowing free use, modification, and sharing for any purpose. Attribution is required: include "Powered by The Grid" linking to https://thegrid.id wherever the data is used. 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