Big Block Interior Protectant 24oz (710ml) Big Block Interior Protectant. Your car’s interior deserves just as much protection as its paint and wheels.Harmful UV rays, the sun’s heat and even intense cold can ruin your interior, making it dry out, fade and crack. Big Block Interior Protectant puts a stop to that – in no time! Its powerful UV blockers keep your interior looking like new. Specially formulated Enthusiast Grade® quality works great on leather, vinyl and plastic. Simply spray on and wipe off for a smooth satin finish that’s never greasy or oily.