SM Arnold Adhesion PromoterItem Code: 66 001 Improves the bond between refinisher and plastics, like PPO, TPO, and metals. Prevents flaking, cracking and peeling. To ensure best results, use this product as a base on rigid polypropylene surfaces like bumpers and door panels. No matter if youre renovating an interior or making a simple repair, refinisher preparation will deliver the results you want.