1/4" x 2" x 4" Black Vers-A-Shim High Impact Plastic Bearing Shimstrips. Designed for use in placing and leveling curtain wall and storefront metal in concrete openings and slabs. Manufactured from high-impact plastic, these shims withstand tremendous loads without compressing or deteriorating due to chemicals, moisture or rust. These solid shims can be drilled in the center to allow placement over the bolt which prevents the shim from possibly moving, as can happen with slotted horseshoe shims. The 2" x 4" (51 x 102 mm) shims snap from the factory sheet of 20 shims. Color:Black Thickness:1/4" Length:4" Width:2".