... ", 2.5", 3", 3.5", 4", 6" 2)Connection size: 1/8" 1/4" 1/2" 3)CE ... 1/2", 3/8", NPT, BSP or BSPT dependent on model & size. Bottom, backleft & right side connectionAVAILABLE RANGES:30Hg ... 1/2", 3/8", NPT, BSP or BSPT dependent on model & size. Bottom, backleft & right side connectionAVAILABLE RANGES:30Hg ... , recalibrators,restrictors, special connections and more. Back Connection Steel Case Gauge 4Z2