We acquired this from our source in Seki, Japan. This is an unmarked prototype Hikari folder (otherwise identical to the marked HK102D2 we have listed). This is a really spectacular high quality knife! It features the traditional Japanese one hand opening and closing mechanism. It has a liner locking mechanism which is unique variation from the original design. It also has a firm ball bearing detent, keeping the blade in place when closed. A truly amazing display of craftsmanship and design.