Right Angle Clamp - 2 - QC Supply

90 Degree Right Angle Clamps Corner Clamp Multipurpose Handheld Heavy Duty Woodworking Tools for Photo Framing Welding Cabinets - AliExpress

2 More Durable 90 Degree Right Angle Clamp – Go Bazaaro

This clamp fits rods up to 18 mm (11/16 in) in diameter.

Right Angle Clamp

2 Pcs 90 Degree Corner Clamps for Woodworking Adjustable Right Angle Joint Clamp

2 More Durable 90 Degree Right Angle Clamp – Go Bazaaro

1/2 Galvanized Right Angle Clamp - QC Supply

Tube Fittings Scaffold Right Angle Coupler Swivel Clamp - China Scaffold Beam Clamps, Scaffolding Joint Clamp

90 Degree Right Angle Clamps Corner Clamp Multipurpose Handheld Heavy Duty Woodworking Tools for Photo Framing Welding Cabinets - AliExpress

Ø1/2 in. Post Right Angle Clamp - PST900