DPC has a line of security bolts that are compatible with our metric (SP10-M8 and SP12-M8) asphalt anchors. All the bolts have a M8 x 1.25 thread. The head is Tri-Groove and requires a special socke (51-6202) in order to install and remove the bolt. The head design makes it difficult to grab with a pliers. When used with the proper socket, considerable torque can be applied to secure the bolt.
The bolts are made from steel with chrome plating. The 41-4017 has a thread length of 33mm.