Our deluxe line of two prong burette clamps are made of pressure die casted zinc alloy and are chrome plated. Adjustable to hold up to 60mm OD burettes, these clamps feature a spring-type adjustment key. Boss head clamp can swing freely and is lockable at any angle up to 360 degrees, and can be used with rods up to 19mm. This 2-Prong Burette Clamp is equipped with a boss head and silicone coated grips, as detailed in the bottom example of photo.