Online Parts Store › Phillips Machine Screw - Flat Head, 3/8"-16 x 4" Image 1 of 1 Phillips Machine Screw - Flat Head, 3/8"-16 x 4" $47.17 18-8 Stainless Steel. Add To Cart Added! 18-8 Stainless Steel. You Might Also Like Stainless Fender Washer 5/8", .109" Thick, OD 2" $37.03 Seachoice 01006 Lock Washer, #8 $15.43 Flat Washer, 1/2", .078" Thick, OD 1-1/4" $38.42 Phillips Tapping Screws - Flat Head, #14 x 3/4" $44.09 Flat Washer, 3/8", .062" Thick, OD 1" $38.36