Muck Boots Calder Wellingtons Muck Boots Calder Wellingtons are built to withstand even the harshest elements, thanks to their 100% waterproof design. Say goodbye to wet feet and hello to dry comfort as you tackle rainy days and muddy terrains with confidence. Fastening:Slip On Material Composition:Other Materials/Textile/Other Materials 100% Waterproof, 100% MUCKPROOF. 4mm neoprene bootie. Breathable mesh sandwich-fabric lining improves air circulation. Durable rubber outsole with quick-cleaning multi-surface traction.. Triple toe and quadruple rubber heel reinforcement for more durability and extended wear.. Pull tab for easy on/off.