Radiator Sleeve. Twin Air is proud to announce their latest product, the Twin Air Radiator Sleeve. This new product is a nylon-coated, glass yarn material that fits over the radiator louvers so no dirt, sand, or mud can stick to the radiator, clogging the radiator, causing overheating. The Twin Air Radiator Sleeve is easily installed by removing the plastic radiator louvers and sliding the Twin Air Sleeve over the louvers and re-installing them on the radiator. Two per package, comes as a complete set.