Desa, 029284T, 100 Pack, .22 Caliber, 42 CW Yellow Powder Fastener Load, 4 x Heavy Load Rate. Desa powder loads provide you with the performance and power you need to penetrate hollow block and concrete. The .22 caliber fastener loads are color coded yellow and are power level 4. Use with low velocity tools and move to next power level if fastener does not set completely. Fastener loads work with Ramset models 721, 4170, M70, RS22, HD22 and Hilt DXE37 and DXE72.