2 Pack of 4 Way Pressure Clamps For Clamping Panels - Using Pressure From All Four Directions. Ideal For Woodworkers and Cabinet and Furniture Makers (2 four way pressure clamps) - Amazon.com
WoodRiver - 4-Way Pressure Clamping System
Campbell Fittings: Heavy Duty High Pressure Bolt Tri-Clamp
1" thru 4" High Pressure Bolted Clamps (13ILB)
13MHP S-Line High Pressure Clamps - Anderson Dahlen