YOEMELY Telesin 6 inch Dome Port for GoPro HERO4 HERO3+ HERO3 + Floating Grip + Trigger + Dome Bag for Underwater Photography

The trigger button is worthless, easier to just use the normal button. It does work well for that half underwater, half out of water imagery (if the water is calm and flat); but the bulb is VERY buoyant, so it can be a hassle to swim with. Good news is that is most certainly floats!

Good quality. I love it