AR-15 Dust Cover (Custom Engraved Caliber) Custom engraved AR-15 Dust Cover allows you to mark the caliber of your AR-15 upper reciever. All caliber specific are marked inside and out. okay boomer is inside only, TPH is out side only. 1 PER PACKAGE COMES WITTH ALL COMPONENTS... MSRP: Was: Now: $14.99 - $16.99 Choose Options