While the Mueller BU-123 grounding clamp is only available in zinc plated cold rolled steel, there are two other versions of grounding clamps that are cast aluminum. The BU-131 and the BU-133 are both similar, with the BU-133 being kelvinized & including a stainless steel wire harness.
Mueller BU-123 heavy duty grounding clamp is zinc plated steel and is rated for 100A. Clamps on to material up to 0.75' thick and has a 4 AWG x 1/4' crimp/solder lug
Mueller BU-123 heavy duty grounding clamp is zinc plated steel and is rated for 100A. Clamps on to material up to 0.75' thick and has a 4 AWG x 1/4' crimp/solder lug