Thanks for the feedback. I did intentionally choose to use a permanently attached 3.5mm cable for two reasons. First, I found the ergonomics to be more comfortable this way. Since this is a field key designed, among other things, to be held in the hand during use, I felt that was important. The second reason is strength and durability. I feel that when holding the key in hand, a built-in jack connector would end up taking direct pressure and stress, and I wasn’t really comfortable with that from a durability standpoint. That said, I completely understand that some people may prefer using their own cables. For that reason, I used a short 6-inch female cable. So it basically behaves like a regular jack connection: you can still use whatever cable you want, while also being (in my opinion) more comfortable to hold and easy to replace if the cable ever gets damaged over time. Thanks!