1.

Metal-Tube Adapters (round)
Model: TAR-50, 38, 32, 28!K
Metal Tube Adapters (round, available in sizes: ID:1/4"~5/16"~3/8" or M6~M8~M10; OD: 5/8"~2")

2.

Metal-Tube Adapters (square)
Model: TAS-50, 38, 32, 28!K
Metal Tube Adapters (square, available in sizes: ID:1/4"~5/16"~3/8" or M6~M8~M10; OD: 5/8"~2")

3.

Metal-Tube Connectors (round)
Model: TCR-50, 38, 32, 28!K
Metal-Tube Connectors (round, available in sizes: ID:1/4"~5/16"~3/8" or M6~M8~M10; OD: 5/8"~2")

4.

Double Metal-Tube Adapters (square & round)
Model: DTAS-50, 38, 28 DTAR-50, 38, 28
Double Metal-Tube Adapters