1/2ips. X 3/8ips. Female Open Cast Iron Hickey This is the largest hickey avaiable in Cast Iron. The 1/2ips (1/2NPS) has a 3/4in. I.D. Hole and the 3/8ips(3/8NPS) side has a 5/8in. I.D. Hole
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Leviton - E-26 Base Porcelain Keyless Socket with Screw Terminals. 1/2ips. Female Die-Cast Cap with Set Screw. 660W 125V/250V
Documentation
UL Documentation