Third Hand Base For Soldering Jewelry. This is a new third hand base. The ball rotates with ease and precision. It has a weighted base for stability. This tool is great for holding jewelry in place while soldering. This can hold up to 5oz of weight at the end of a pair of tweezers. It measures approximately 1 3/4" (44 mm) high and 2 1/2" (62 mm) in diameter.