You pick up the device. It is rather heavy, and might be a little easier to manage if you had not just lost a lot of your arm strength by turning into a woman.
As you struggle to keep it help up, you accidentally flip a switch on the side. The device starts to glow and vibrate, causing you to drop it.
The devices shakes and fired a beam of energy straight back at you.
After it hits, you feel energy coursing through your entire body. Your breasts shrink as your body mass noticeably increases. The hair on your head retracts into your body as you feel your body hair growing back elsewhere. A familiar tug beneath your legs marks the return of your manhood.
You pick the device back up, and it is much easier to handle this time. You study it in amazement as you realize that it has the ability to create beams, bullets, and waves of energy with the Gender Wave ability!