Irwin 18" Quick Change Bar Clamp/Spreader has a 3-3/16" throat depth and a 300 lb clamping force, making it ideal for heavy-duty applications. The clamp is made of an I-beam bar to reduce flexing and bowing, and it has a classic pistol grip design and a quick release trigger for one-handed operation. The clamp also has a quick change button to easily convert it into a spreader or a specialty clamp with the installation of one of the 1 handed bar clamp accessories.