The pin mats have small cylindrical projections on the top which prevents the dirt and debris from entering a home.This Mat can be placed in a mud room, garage or foyer so you can wipe your feet when you come in from skiing, hiking, gardening or just playing outside.easy to clean, just sweep, shake out or vacuum. •Made from 100% rubber•The rubber pins provide excellent brushing action, extra durable and long lasting weather resistant door mat contains no environmentally damaging PVC•Thin pile prevents tripping, molded design will not crush or break down over time or use•Indoor/outdoor use, resistant to mold and mildew•Easy to maintain, shake/sweep clean or wipe with lukewarm water