Willapa Marine Crab Bait Barrel - Engineered for crab and shrimp traps, these bait barrels are proven both effective and convenient. Their cylindrical design features vinyl-coated wire mesh with plastic housing at both ends; one with an attachment snap and the other with a screw-on lid for filling with bait. For Crab and Shrimp Traps. Cylindrical Design Screw-on Lid Snap Attachment Dimensions: 3-5/8in x 9in