Is For: (inventory 37-4-1) KOSSEL 3D 3X PULLEY 20T 5MM &. KOSSEL BELT KIT. QTY 3 PULLIES 20T 2MM PITCH 5MM SHAFT UP TO 7MM WIDE. WIDE 2MM PITCH. FEED FAMILIES NOT CORPORATIONS. This rubber timing belt is highly resistant to wear and is ideal for 3D printers and linear motion applications.