Online Parts Store › Phillips Machine Screw - Oval Head, 5/16"-18 x 1-1/2" Image 1 of 1 Phillips Machine Screw - Oval Head, 5/16"-18 x 1-1/2" $31.36 18-8 Stainless Steel. Add To Cart Added! 18-8 Stainless Steel. You Might Also Like Square Tapping Screw - Oval Head #10 x 1-1/4" $57.05 Phillips Tapping Screws - Oval Head, #12 x 1-1/4" $22.30 Phillips Tapping Screws - Flat Head, #6 x 1/2" $9.26 Stainless Fender Washer #10, .050" Thick, OD 3/4" $18.58 Stainless External Tooth Lock Washer 5/16" $19.48