Thank you for viewing. Sanwa USB-connected numeric keypad with Num Lock function. - Brand: Sanwa - Connection Type: USB - Key Arrangement: Numeric Keypad - Features: Equipped with Num Lock function Due to poor contact, it sometimes works and sometimes doesn't. It's the type with an extendable cord and doesn't require batteries. Other than the poor contact issue, there are no other problems with the buttons, etc. I'm not sure if there's a demand, but please consider purchasing only if you understand the above!