Primos 608 608 Jelly Head Turkey Choke Tube Mossberg 12GaPrimos Jelly Head Choke Tube 12 Gauge Mossberg 835/935 #608 jelly Headâ Choke Tubes are crafted with the most demanding turkey hunters in mind. This extralong extended choke is CNC milled from chrome alloy steel. They are designed to increase the range and pattern density of HEVI SHOTÂ, copperplated lead or regular lead. The fluted ports allow gases to vent quickly behind the load of shot instead of blowing through it and causing pattern distortion. The ports also help reduce felt recoil and muzzle jump. These screwin turkey choke tubes have a knurled end, which extends beyond the end of the barrel for easy installation and removal without the use of any tools. Jelly Headâ Choke Tubles have a 90% pattern density at 40 yards.FeaturesThis Choke Tube features a .690 constrictionSpecificationsGauge: 12