Woodline USA WL-5234 ProGrip 37-Inch Back-To-Back Professional Clamps 37-inch back-to-back professional clamp ideal for sanding and finishing, planing, gluing, assembly, routing, and sawing 2 edge mount T-slots in top combined with T-bracket locks clamps together Rock solid base constructed from ultra-heavy aluminum Includes center mount measuring tape for simple off-set marking 37-inch opening capacity; 3-position lock lever