Tinkering with your 3D printer? These die springs are a popular upgrade, especially for bed leveling on printers like the Creality Ender series. The pack comes with 10 red springs made from spring steel, painted to resist rust. They’re a medium load type, which means they have a good balance of stiffness and give. Dimensions: 14mm outer diameter, 7mm inner diameter, and 20mm free length (give or take a couple mm). They’re designed to replace the stock springs under the print bed, providing more consistent tension and helping your bed stay level longer. The compression ratio varies with use cycles (up to 0.32 for 300k compressions). While they’re made for industrial die machinery and plastic injection molds, 3D printer enthusiasts have found them perfect for improving print quality. An inexpensive upgrade that can make a big difference in your prints’ first layer adhesion.