CGA 510 Inlet Nut and Nipple with Filter. For Acetylene regulators. This nut and nipple is for the Old Style of Uniweld regulators only
The Old Style has the seat assemble (parts #7, 8, and 9) that is accessed through the front of the regulator as pictured in the breakdown.
Regulator pictured in breakdown is a R-B and is for reference only.