Lindapter Hollo-Bolts are perfectly suited for use in hollow sections, tubes and places where access is available from one side only. They were awarded the Design Council's Millennium Product status for innovation in 2000 which has made them the standard for blind steel connection. For added corrosion protection, the Hollo-Bolt comes with additional JS500 protection as standard or hot dip galvanized. Sizes 5/8" and 3/4" have patented collapse mechanism for optimized clamping force. They allow for speedy installation with standard tools. Lindapter Hollo-Bolts are available in a variety of lengths, materials and sizes.