Home / Accessory-Barrels / Heckler and Koch (HK USA) THREAD CAP MARK 23 View cart “Walther Arms BARREL Q5 SF 9MM 5.5″ THREADED” has been added to your cart. Heckler and Koch (HK USA) THREAD CAP MARK 23$3099 Only 1 left in stock Heckler and Koch (HK USA) THREAD CAP MARK 23 quantity Add to cart SKU: 970174 Category: Accessory-Barrels Product ID: 41553 Description Description Related products Sale! Shadow Systems BARREL 9MM FS BRZ FLT TB $23400 Original price was: $23400.$19156Current price is: $19156. Sale! Shadow Systems BARREL 9MM FS BRZ FLT $21100 Original price was: $21100.$17348Current price is: $17348. Walther Arms BARREL Q5 SF 9MM 5.5″ THREADED $24900 Sale! FN BBL AR-15 5.56MM 10.5″ M16 CAR $29900 Original price was: $29900.$27441Current price is: $27441.