Our Mission: To protect, preserve and promote the natural integrity of Radnor Lake through land acquisition, environmental education and park support.
Chains up to 12 mm thick are generally portable: you can carry them around on your bike every day. The long ones will be really heavy though, so please check the weight. Above 12 mm the chains are more suitable as stationary locks: you would leave them wherever you lock your bike for long periods of time.
I doubt you could find anything heavy enough to overload a 2x4 piece of 3/4 ply. The framework around the edges would break first. I would estimate aprox 1500 to 2000 lbs evenly spread. #3 Dec 3, 2002.