EXTENDED CHOKE WITH DIAGONALLY-PORTED DESIGN FOR RECOIL REDUCTION. CONICAL/PARALLEL INTERNAL CONFIGURATION.
EASY TO INSTALL AND REMOVE WITH YOUR FINGERS. NO SPECIAL WRENCH OR TOOL REQUIRED. 
FITS BARRELS WITH MOBILCHOKE STYLE THREADS.
BERETTA HAS MULTIPLE THREAD SYSTEMS THAT ARE NOT INTERCHANGEABLE. 

OVERALL LENGTH: 3 9/32"
PORTED SECTION LENGTH: 1 1/4"
IN-BARREL LENGTH: 2 1/16"
STANDARD BORE SIZE: .625"
MATERIAL: 17 - 4 STAINLESS STEEL