4pcs Heat Bed Strong Yellow Springs OD8 ID4 L20

It's built with rectangular shape section, tougher and keeps print bed level better. The thumbwheels under your heat bed might be rotated itself and the weak springs get loosen after long-run printing (due to movement or vibration). If you're tired of leveling your bed constantly, better springs are a very inexpensive upgrade to your 3D printer! With this kind of strong springs, you won't need to level your bed between prints nearly as often.

Specifications

• Outer Diameter (OD): 8mm
• Inner Diameter (ID): 4mm
• Length: 20mm