SPE-M3-4-HB NBK Plastic screw Hex Posts made in JapanSPE M3 4 HB NBK Plastic screw Hex Posts made in Japan Quantity: 5 Screws PEEK is a thermoplastic super engineering plastic with excellent physical and chemical properties. These screws have excellent chemical resistance. They are mostly unaffected by chemicals excluding concentrate sulfuric acid, concentrate nitric acid, and concentrate hydrofluoric acid. These screws have excellent heat resistance, water resistance, and high heat resistance strength.