Home Hardware & Fasteners Machine Screws Phillips Head Machine Screws – Flat Head (1/4-20 x 3”) Marine Fasteners Inc Phillips Head Machine Screws – Flat Head (1/4-20 x 3”) $17.09 Phillips Head Machine Screws – Flat Head (1/4-20 x 3”) quantity Add to cart Product Details Product Details 1/4-20 x 3″. Stainless steel. Sold in boxes of 25.