Yankee Hill Machine Improved Cylinder Co VICTRA-12 Choke Tube Silver. The choke of a shotgun determines shot string only. It has no bearing on shot speed (velocity) or distance (range). That is the choke does not alter the shotgun's power it just controls how tight or spread out the pellets will be at a specific distance. Specifications for Yankee Hill Machine Improved Cylinder Co VICTRA-12 Choke Tube: Manufacturer: Yankee Hill Machine Caliber: 12 Gauge Fabric/Material: 17-4 Stainless Steel Color: Silver Gauge: 12 Finish: Stainless Diameter: 1.05 in Length: 1 in Choke Type: Improved Cylinder Package Contents: Yankee Hill Machine VICTRA-12 12 Gauge Choke Tube1 Yankee Hill Machine YHM-1240: Improved Cylinder Co VICTRA-12 Choke Tube Silver