Hammerite Underbody Shutz with Waxoyl 1L. Underbody Shutz is black coloured, one coat, heavy duty protection against rust. Proven corrosion resistance, increased protection and extended vehicle life. This Hammerite Underbody Shutz with Waxoyl remains flexible,resists cracking or peeling.Hammerite Shutz has a non-drip super smooth application.It is free from gritty and abrasive particles.Supplied in 1L