Online Parts Store › Phillips Machine Screw - Oval Head, 5/16"-18 x 4" Image 1 of 1 Phillips Machine Screw - Oval Head, 5/16"-18 x 4" $34.64 18-8 Stainless Steel. Add To Cart Added! 18-8 Stainless Steel. You Might Also Like Phillips Tapping Screw - Pan Head, #14 x 3" $61.60 Seachoice 01006 Lock Washer, #8 $15.43 Phillips Tapping Screw - Pan Head, #10 x 1-3/4" $26.26 Carriage Bolt, 1/2"-13 x 3" $92.78 Nylon Insert Locknut - Stainless 5/8-11 $35.08