6.6mm sight will rise point of impact on USP full size pistols approximately 2 inches at 25 yards.

6.6mm sight will lower point of impact On USP Compact approximately 4 inches at 25 yards. 

Fits:

• USP9
• USP40
• USP45
• USP9 Compact
• USP40 Compact
• USP45 Compact

Does NOT fit USP Expert/Elite