Yes, all VG6 Muzzle devices include a crush washer.   The Aero Precision birdcage styles DO NOT include a crush washer.  Additional crush washers are available for purchase in 1 or 5 packs.  Remember, crush washers are good for one use only.  Additional washers are useful if you ever need to uninstall your device to swap out a gas block or you intend to use your muzzle device on another rifle in the future.  Simply use the search box on our website to quickly locate these items.