The advantages of nylon lens are: high mechanical strength, good toughness, high compressive and tensile strength, and the tensile strength is higher than that of metal, which is equivalent to that of metal, but the rigidity is higher than that of metal and the yield strength is twice that of ABS. After repeated twists and turns, the fatigue performance of the protruding diameter can still maintain the original mechanical assistance. Common brake ladders, handrails, heart-shaped bicycle plastic rims and other occasions with obvious periodic fatigue effects are often applied with high softening point and high heat resistance.