Keep your hardshell hardcore. The Nikwax Hardshell DuoPack contains a 300ml bottle of Tech Wash and a 300ml bottle of TX Direct Wash In. Tech Wash is a non-detergent, biodegradable liquid soap which removes dirt and detergent residues while leaving the water-repellent finish on waterproof clothing, equipment and sleeping bags intact. Nikwax TX Direct Wash-in adds water-repellency and revives breathability to your waterproof/breathable garments.