The LadderM8rix Professional ladder safety device can be used on most hazardous exterior surfaces, including grass, oily concrete, tarmac, decking, paving slabs, gravel, snow and even solid ice. The reason it boasts that it can go on all these surfaces is because of the exclusive metal 2,000-pin spiked base that engages the surface. The Professional has a rubber anti-slip top pad where the ladder feet are placed and comes complete with carrying case. This model is recommended for outdoor use only. For an indoor/outdoor model, try the Ladder M8rix Pro-Plus.