Online Parts Store › Phillips Machine Screw - Pan Head. 5/16"-18 x 1-1/2" Image 1 of 1 Phillips Machine Screw - Pan Head. 5/16"-18 x 1-1/2" $42.20 18-8 Stainless Steel. Add To Cart Added! 18-8 Stainless Steel. You Might Also Like Stainless Countersunk Finishing Washer, #8 $14.36 Lock Washer, M5 $10.83 Phillips Tapping Screw - Truss Head #10 x 1" $33.32 Lock Washer,1/2" $24.75 Phillips Tapping Screws - Flat Head, #6 x 1-1/4" $15.93