QSC 20 Pack Aluminum Countersunk Conical Washer Set, Spacer, Valance, Tapered Go to amazon.com Related posts The 8 best countersunk washer FeatureMaterial: 6061 AluminumBore: .250Width: 1.125Height: .150Hardware Included: Flat Head Socket Cap Screw 1/4-20 Thread X 1" Length, 1/4 Flat Washer & 1/4-20 Nylock Nut DescriptionQSC 20 Pack Aluminum Countersunk Conical Washer Set, Spacer, Valance, Tapered