For this we recommend using SONAX Plastic restorer black or XTREME Plastic restorer gel exterior Nano Pro The products restore the colour of unpainted plastic parts and seal the surface against aggressive environmental influences. This works with already weathered and faded bumpers and, of course, also with parts as good as new. The pre-treatment is of particular importance: thoroughly clean the surface before applying the product. To achieve even and streak-free results slightly moisten the surfaces to be treated with a sponge or cloth. Afterwards, apply Plastic restorer and wipe with a damp sponge.