The Wmd Guns AR-15 Nib-x Complete Bolt is an essential upgrade for your AR-15 rifle featuring a robust Nickel-Boron finish for enhanced durability and smooth operation. This versatile bolt is compatible with multiple cartridges including the AJJ_223 Remington AKK_5.56 mm NATO and CCP_300 AAC Blackout making it a perfect choice for shooters seeking reliability and performance across different calibers. Designed to meet the demands of any shooting scenario this complete bolt enhances your firearm's functionality while maintaining the trusted quality associated with the AR-15 platform.