Description This item is a set of 3D Printer accessories. These tensioners are made from quality metal which means that it can bear heavy streess while retaining its original shape. Great replacement to replace the crappy ones that come with 3D Printer. Just always make sure the the size is the same as the one you want to replace. Feature - Color: Silver - Material: Metal - Size: 1.5x0.x0.5cm/0.6x0.2x0.2inch - It is designed for linear motion and precision. - They keep great tension on the belt. - Easily added the right amount of tension to the belt. - Keep the belts snug and this will make your printer much more precise. - Bear heavy streess while retaining its original shape. Package list: 1 x set of 10pcs GT2 Timing Belt Tensioner Torsion Spring for UM2 Ultimaker2 3D Printer