what flabbergasts me is the fact that they cost $40/pair (unless someone can point me to a cheaper option)
From the site:
"PEEK is high temperature resistant engineered thermoplastic with excellent chemical and fatigue resistance plus thermal stability. They exhibit superior mechanical and electrical properties. With a maximum continuous working temperature of 480 ° Fahrenheit, they have excellent retention of mechanical properties up to 570° Fahrenheit in a steam or high-pressure water environment. Superior chemical resistance has allowed them to work effectively as a metal replacement in harsh environments. They are inert to all common solvents and resist a wide range of organic and inorganic liquids. When extensive machining is required, a secondary annealing process should be considered.