Thermal Sensor and Wire connector covers are a great way to protect sensors plugs and wire connectors from heat, moisture and dirt. They are made from an aluminized insulation that will reflect heat and act as a thermal barrier for sensitive wire connections and sensors. Simple to install with a split top to cover connectors near engine manifolds, turbos, and their heat sources. Includes: Two (2) covers, 25mm I.D. x 2 in. with 28.2mm O.D.