NIKWAX COTTON PROOF. Apply Nikwax Cotton Proof in the machine’s dispenser. Alternatively, just apply Nikwax in a simple hand wash. Wash-in waterproofing for cotton, polycotton and canvas. For dry cotton tents, dilute with 6 parts warm water (1:6) and for wet cotton tents dilute with only 2 parts warm water (1:2).
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