Tamrac M.A.S. Large Raincover (Black) Tamrac's M.A.S. Raincover - Large can be used for extra security in bad weather. Tamrac photo backpacks are made from waterproofed materials and have giant rain flaps to protect the zippers, so in general, they don't require a raincover. However, these raincovers provide added security in extreme weather Folded into their pouch, they attach to any of the M.A.S. backpack attachment points. Fits Models 777, 787, 5258, 5550, 5588 and 5589.