Made in Japan, this is a professional industrial tool. Unlike the dozens of cheap varieties of 1/4" drive Gamebits found online, this is an actual driver, capable of reaching deeply recessed screws.
Used on many video game cartridges and other devices, this type of fastener is most commonly called by it's incorrect nickname of 3.8mm Gamebit. The correct fastener type and size is 3.6mm Line Head Screw.
평생 품질 보증