Salsa EXP Series Cholla Half-Frame Bag - Size 3 GraySalsa EXP Cholla Half Frame Bag Size 3. The EXP Series Cholla Half Frame Bag keeps ride needs easy to reach but doesnt block bottles. Six sizes help maximize space (and aesthetics) on a wide range of Salsa frames and other bikes too. And forget about strap rub with direct mount capability on compatible Salsa frames. The Bluesign approved Cordura nylon and molded tooth zippers will stand up to dusty trails and daily use. Load up this half frame bag and