A 12″ handguard is a mid-to-long rail or polymer handguard designed for AR-15 and AR-10 rifles with barrels typically ranging from 12.5″ to 16″. It works with carbine, mid-length, or rifle-length gas systems, compatible upper receivers, low-profile gas blocks, and gas tubes. The 12″ handguard offers generous space for mounting accessories like lights, grips, and sights while providing a balanced profile, making it ideal for tactical, competition, and custom AR-platform builds.