Online Parts Store › Stainless Countersunk Finishing Washer, #4 Image 1 of 1 Stainless Countersunk Finishing Washer, #4 $13.29 316 Stainless Steel. Add To Cart Added! 316 Stainless Steel. You Might Also Like Nylon Insert Locknut - Stainless 7/16-14 $21.10 Phillips Tapping Screws - Flat Head, #14 x 1" $45.79 Square Tapping Screw - Oval Head #8 x 1-1/2" $54.12 Nylon Insert Locknut - Stainless 12-24 $75.96 Phillips Tapping Screws - Flat Head, #6 x 3/8" $9.01