The Stinger CH38-2 is the first hammer tacker to deliver a cap and a staple. 1 In. plastic cap and 3/8 In. staple are driven at the same time. Pull trigger to advance cap and then use like a standard hammer tacker to drive the staple. Cap fasteners are a recommended installation best practice by house wrap manufacturers because caps help seal out moisture that penetrates side walls. Designed for use with 3/8 In. Stinger StaplePac only, Model No. 136420.