FANTASTIC polyester filler is a two component multifunctional paste used for the filling of holes and imperfections in most substrates. FANTASTIC has been specially formulated for the professional using the latest technology in lightweight body fillers, and it combines excellent filling properties together with the easiest sanding of all the U-POL fillers. FANTASTIC polyester filler can be used on the following surfaces:- - Bare metal - e.g. Steel, Aluminium and Zinc coated substrates. - Original paint surfaces (with the exception of thermoplastic acrylics). - GRP.