Yes, muk mats can be left in the sun. All muk mats are UV protected; however, as with any plastic material, the artificial turf can be damaged by intense heat. This can result in anything from curling corners, flattened blades or damage caused by refracted light. Refracted light can be from materials such as glass, aluminium checker plate step sides and stainless steel.  Refracted light damage is rare, but please take care to avoid by storing your mat out of direct sunlight to prevent overheating and melting of the plastic blades. Items left on your muk mat for a period of time may heat up and leave permanent marks on your mat. You can read more here on our blog.