This set of two bar clamp couplers are designed to work with Irwin's medium-duty 300LB clamps, providing a secure and reliable hold for your woodworking projects. The couplers are made from durable ABS plastic and come in a sleek black color that complements the clamps' design. With these couplers, you can easily expand the reach of your clamps and tackle larger projects with ease. The quick-grip feature makes it easy to adjust and secure the clamps in place, ensuring your workpiece stays in place throughout the project. Whether you're a seasoned woodworker or just starting out, these couplers are a must-have accessory for your toolbox.