Product Description The Raptor Adapter is a thread conversion piece which takes the proprietary base-end TPI of the Raptor series and converts it to the industry standard 1.375 x 24 TPI. Ab Suppressor Raptor Adaptor 1.375-24 at Shooting Surplus Browse all Shooting Surplus deals $29.24 In Stock at Shooting Surplus Price verified 3d ago Buy Now at Shooting Surplus Secure checkout Easy returns or compare prices Amazon eBay Product Details Brand Ab Suppressor Gun Parts Ab Suppressor