The SML Shield range are commercial primers formulated for easy application by leisure users who do not have access to spray equipment. Available in 2.5L tin sizes they provide a cost effective alternative to other products. For all metal substrates Shield Surface Tolerant Epoxy Primer is recommended, bonding well to bare metal and being tolerant of less than perfect preparation. For bare GRP, Shield High Build Epoxy Primer can be used to repair and build up the GRP / gelcoat layer, and is easily sanded to provide a smooth finish ready for your topcoat. For previously painted surfaces Shield Undercoat above the waterline and Shield Underwater Primer below the waterline form a good base for your topcoat or antifouling