Are these mats mildew resistant? Is there ventilation underneath? I’m planning on installing these in a garage, and water may get on and under them.

Our 3/4" Extreme Mats are mold and mildew resistant. These rubber mats are not vented, so there is no ventilation underneath the mats. Any water that pools under the mats will eventually evaporate. Depending on how often water pools under the mats, we may recommend pulling the mats up to allow the water to evaporate properly.