Gorilla Blackjack Waterproofer 20 litre Black SKU: 360292 MODEL: 36689 Error. try again later You've successfully joined the club $ 142 .08 each Mitre 10 SAvailable at selected stores. Check your local store for details Variants Water based, high performance, ready to use liquid waterproofing membrane. Features and benefits Damp proof retaining walls. Waterproofing basement structures. Building blocks, concrete, brick, wood and metal. Easy to apply and clean up.