100A Round Meter Base 1)Material: metal or copper 2)Size:1/2", 3/ ... low amperage requirementsSpecification Item Code No. Description Fix hub sizeSM-100-B1 Phase,100A,120/240Vac,4 jaw 1/2"SM ... -100-C1 Phase,100A,120/240Vac,4 jaw 3/4"SM-100-D1 Phase,100A,120/240Vac ... ,4 jaw 1"SM-100-E1 Phase,100A,120/240Vac,4 jaw 1-1/4" ...