Online Parts Store › Carriage Bolt, 3/8"-16 x 4" Image 1 of 1 Carriage Bolt, 3/8"-16 x 4" $37.85 18-8 Stainless Steel. Add To Cart Added! 18-8 Stainless Steel. You Might Also Like Phillips Tapping Screws - Flat Head, #8 x 1-1/4" $19.34 Phillips Tapping Screws - Flat Head, #6 x 5/8" $9.57 Square Tapping Screw - Flat Head,#8 x 1" $27.12 Phillips Tapping Screw - Pan Head, #8 x 3/4" $19.21 Phillips Tapping Screw - Pan Head, #12 x 1-1/4" $23.49