Suppliers of Resin Bound Materials to DIY and Trade customers. SUDwell Resin Bound Gravel Kits are easy to install and quickly transform your driveway path or patio. Our Resin Bound Kits are eco-friendly, maintenance free and conform to S.U.D.s regulations (Sustainable Urban Drainage), so you wont need planing permission to install or use them on your driveway. Our DIY kits are fully permeable (so no puddles), and now come in a range of 10 earthy natural stone colours.