You can buy as many zinc-plated mushroom Spike® fasteners as you need

1/4 x 18 High Speed Aircraft Bit

7/8-9 x 18 Socket Cap Screw Alloy

1/2-20 x 5 1/2 Hex Cap Screw SS 316 (A4)

3/8 L9 SAE Tension Flatwasher Yellow Zinc Plated Domestic USA (100) 1/2-13 L9 Hex Cap Screws Yellow Zinc Plated - Domestic USA You can buy as many3 8 L9 SAE Tension Flatwasher Yellow Zinc Plated Domestic USA (100) . L9 High Tension SAE pattern flat washers are designed for use in high stress, severe service environments. The highest mechanical strength off the shelf fastening system available, its special features control torque tension characteristics to develop high clamp loads when using properly controlled tightening methods.