Originally Posted by
fietsbob
Poly carbonate is also Lexan a trade mark the bubbles on Battle tested airplanes are made of that .
Struts are the stiffeners
SKS is a thermoplastic It is made over a Metal core ..
Martin Makes guitar cases with ABS thermo plastic Shells
The SKS "thermoplastic" fenders are about as stiff/rigid as a dry bowed postal envelope you get your paycheck in. Although the SKS have double the stay bracing points as the Planet Bike, the SKS are still quite whippy IME and therefore prone to inducing noise and tire wear due to contact when riding on anything other than good roads.
Least that was my experience with their longboard 35mm fenders.