[Sintron] 2M Timing Belt Set + 2 pcs GT2 20 Tooth 5mm Bore Pulleys for RepRap 3D Printer Prusa Mendel i3 Kossel Delta ect. (1) Improve your print quality with GT2 belts and pulleys . (2) GT2 belts are designed for linear motion, unlike T2.5 timing belts . (3) Improve your print quality with high quality belts/sprockets designed for precise linear motion. (4) We not just sell them, we also provide professional after-sales service, so welcome to discuss with us, we will try to do technical support as much as we can.