Centurion Arms' new bolt design will make your AR platform more reliable and last longer with a lifetime guarantee against bolt breakage. Our new bolt has a body profile that creates a larger radius between the bolt lugs and the body that allows the pressure to be spread over a larger area reducing stress points which leads to lug failures. We have also added dual ejectors that help rotate the brass off the bolt face faster to ensures more reliable ejection in rifles while running suppressed or going back and forth between suppressed/unsuppressed. This also helps with platforms that are considered to be "over-gassed".Our V2 bolts use a standard lug profile and can drop into any mil spec barrel extension.V2 bolts use standard gas rings for logistical commonality and also use standard extractors with black inserts and either Colt OEM extractor springs or our upgraded 5 coil chrome silica stress relieved spring for ultimate reliability (EXT-SPRING) .Lastly, our V2 bolts do not require a proprietary firing pin or cam pin so please feel free to mix and match with your favorite standard selections as well.Barrel Extension Compatibility:V2 bolts are compatible with BOTH Standard M4 Extensions and Centurion Arms "T" Marked Extensions. Our V2 bolts are NOT compatible with KAC E3 extentions; please see our E4/ETB bolts instead.Features Hard chrome Dual ejectors for more positive ejection and greater reliability Shot-peened Magnetic particle inspected Tool steel extractor