Hi Trident,
the one I got was actually USB.
It even has 2 usb ports onboard, though not sure how well they work ie if they'd cause latency if I used a controller via the keypads ports.
At the moment I'm using it with an old win98
64mb celeron laptop which has 2 usb ports anyway, so not an issue.
The bizzare part is I think I paid $3-99 AUD for the keypad & $14AUD postage from hong kong. Figured it was worth a try.

I blew my Dell xp laptop up, I didn't realize I hadn't switched it off properly and left it sitting on a soft surface. When I moved it , it reactivated & went into melt down. Still can't beleive it happened and that I was so careless. Suppose live& learn.

best wishes
Rikki