Yes, DiamondFinish Clear almost always adheres very well to plastics especially high solids plastics. Be sure to clean the surface well with KBS Klean before the application of DiamondFinish Clear.
Yes, DiamondFinish Clear almost always goes over vinyl stickers really well and protects the sticker. Please be sure the initial sealing coat of DiamondFinish Clear is nice and thin. As always, test an inconspicuous area first.
Please be sure to review the Complete DiamondFinish Clear Application Directions before you begin your project.