Let's get it right to the point: Rubber has nothing to do with plastics. Quite contrary, rubber is a natural product and most plastic care products have no business being applied on rubber parts (for plastic care we recommend you to use Swissvax Protecton).
Rubber tends to get brittle, chalky, cracked and unsightly over the years and unfortunately the replacement of all rubber seals on an automobile is very costly and for many older cars these seals even aren't available any longer. Therefore regular care of all rubber parts is very important to keep your automobile in "factory-new" condition for a very long time. Seal Feed was developed exclusively for rubber and keeps rubber seals pliable and fresh for years.
Even if at first glance the often neglected seals may only seem to be a detail of your automobile make sure to pay attention to them.
For chalky greyed out seals please clean them first with a ph neutral cleaner (e.g.Swissvax Leather Cleaner or Plastic Wash) then apply Swissvax Seal Feed