The KWA H&K USP Compact blowback cylinder or blowback chamber replaces the original blowback cylinder. This is the part to replace if yours is cracked or is not feeding BBs out of the magazine.
KWA HK USPC Part 6. Does not include internal valve and spring.
All KWA parts are top-quality replacement or repair parts, and are the only parts recommended for use with KWA Gas Blowback Pistols.