High Performance Signature Extended Investor Plus Choke Tubes The time has come for a set of true, high performance tubes to match the requirements created by the expanded line of Winchester shotguns. They set a standard as the finest Winchester choke tubes ever and offer performance competitive with the finest choke tubes on the market Features: - 17-4 Stainless steel in natural finish- Extended design (3/4" beyond muzzle) with Winchester Signature "Red" band on front edge- Completely compatible with steel shot, lead short and heavy shot- Perfect concentricity for more uniform patterns- Knurled surface for easy insertion.- Investor Plus slots included for using a wrench- Precision internal and external dimensions Specifications: - Bore:.730- Constriction:.010.