stb-18a a mechanical numeric keypad usb/ps2

please note that before buying, please choose your required interfaces, the usb or ps / 2 if there is no marked interface, we will random shipment a mechanical numeric keypad product description 1, the number of keys: 18 key shell material: plastic 2, key-press material: imported key core key life: more than 5 million times 3, keycap: laser engraving or silk screen keyboard interface, usb 4, working voltage: + 5 v 5, working current: < = 100 ma 6, size specifications: h34 w103 l140 * * mm