Online Parts Store › Nylon Insert Locknut - Stainless M5-.8 Image 1 of 1 Nylon Insert Locknut - Stainless M5-.8 $15.56 18-8 Stainless Steel. Add To Cart Added! 18-8 Stainless Steel. You Might Also Like Carriage Bolt, 1/2"-13 x 5" $49.07 Flat Washer, 3/4", .109" Thick, OD 1-7/8" $47.99 Stainless External Tooth Lock Washer 5/16" $19.48 Stainless Cotter Pin 1/8" x 1" $63.67 Nylon Insert Locknut - Stainless 5/16-24 $46.35