All Shocktech Spyder Bolts are designed with our trademark modified 3 hole Venturi concave face.. Delrin anywhere the bolt comes in contact with with metal and aircraft quality aluminum backbone. Everytime they make a new Spyder we gotta make a new bolt! But since there is 10 bazillion Spyders, we thought it would be a good idea to keep up! No need for long drawn out explanations, simply put they make a great and we make a great bolt. You can expect more shots from you tank along with improved shot to shot consistency. This is the best 40 bucks you'll spend on your gun period.