Additional Service: USC/UMP Flattop Upper Modification$39900 Categories: Build Your Own, hide-from-search, Work Orders Product ID: 6056 Flattop, picatinny, full length top rail modification Additional Service: USC/UMP Flattop Upper Modification quantity Add to cart Description Description Flattop, picatinny, full length top rail modification You may also like… Out of stock WAITLIST NOW Black Polymer HK Vertical Grip 416 G36 UMP MP5 $3900 Out of stock WAITLIST NOW HK USC/UMP 45 8″ Threaded Factory Barrel $49900 Out of stock WAITLIST NOW HK UMP/USC Picatinny Accessory Foregrip Rail Set $9900 Out of stock WAITLIST NOW HK UMP/USC Picatinny Optic Top Rail Trade In $3900 Related products Out of stock WAITLIST NOW HK UMP 40Cal Conversion Kit Bolt and Barrel from: $39900 Out of stock SALEWAITLIST NOW HK UMP 10mm Conversion Kit Bolt and Barrel from: $69900$49900 Login Register Login Password Forgot password? Remember me Login E-mail I agree that my submitted data is being collected and stored. For further details on handling user data, see our Privacy Policy Password Confirm Password Minimum 4 characters