Grip Rite Prime Guard GRLMIX 18 Gauge Electrogalvanized L-Style Narrow Crown Staple Mix Pack, 1/2"/3/4"/1" For best results, use Grip-Rite GRTSN100 & GRTSN150 1/4" Narrow Crown Staplers Compatible with most 18 Gauge Narrow Crown L-Style Staplers Should not be used in treated lumber. Should not be used where surface rust is unacceptable. 1/4 Inch Crown