Pushing it down past a spring stop serves to decock the pistol. The middle setting is go. The Expert's magazine release is an ambidextrous lever at the back of the trigger guard that is pushed down to drop the magazine. It is virtually impossible to unintentionally release the magazine. The USPs do not have magazine safeties, but they do feature an accessory rail.
Sights are excellent.
There's a nice wide front sight in a dovetail and the rear sight is fully adjustable for both elevation and windage. Nothing unusual here. TEST HK Expert USP Ammunition Velocity Accuracy Fed. Golden Saber 230 gr. Winclean 185 gr.