The Army Painter GameMaster - Terrain Sealer: Matt Sealer, (10 Ounce) - Matte Spray Paint Primer with Matte Filler Primer for Crafts, Dungeon Dragon Terrain Tiles, & Tabletop Wargaming Scenery. - - Amazon.com
Morrells | 329 Clear High Build Pre-Catalyst MDF Sealer
KILZ Original 13 oz. White Oil-Based Interior Primer Spray, Sealer, and Stain Blocker 10044 - The Home Depot