Those are *Pipe Flanges, Reducers & Bolting* - Industrial piping components.
*What it is:*
1. *Top shelf*: Weld Neck Flanges + Concentric/Eccentric Reducers. The blue plastic covers protect the sealing faces.
2. *Middle shelf*: Slip-On Flanges, Blind Flanges, and other RF/FF flanges stacked. Various sizes and pressure classes.
3. *Bottom shelf*: Heavy-duty stud bolts + nuts for flange assembly. Long threaded rods with galvanized finish.
4. *Material*: Looks like carbon steel / stainless steel. Common for oil & gas, refinery, and process piping.
*What it’s used for:*
Connecting pipes, valves, pumps, and vessels in oilfield, refinery, and industrial plant piping systems. Used for pressure piping, flow lines, and process