While most vent lids are build out of extremely durable material, they can get damaged over time.

Often it's the sun that slowly breaks them down, but an accident or other influences can cause it the crack as well. Instead of having to replace the whole vent you can simply exchange the vent lid.

This Jensen 14" x 14" "O" Style Lid is a replacement part for your Jensen or Heng MK1 vents if they were manufactured before 1990.