How long should the bolts be for your plow edge installation? Long enough to reach through the metal mounting strap which is typically 1/8” to 1/4” thick, through the rubber plow edge which is commonly 1/2” thick to 1” thick and also through the plow’s moldboard and base. Generally, the minimum length of the mounting hardware for installing a rubber edge is 1.25”. You also want to avoid the bolts being too long, as they can be long enough to scratch or otherwise damage the pavement surface being cleared.