Class 1 marking material is used in the manufacture of markers that are permanent in nature. The markers are then to be applied, by means of their adhesive layer, on exterior and interior surfaces of automotive vehicles, aerospace and ground support equipment, on interior surfaces of aircraft, and in other applications as required or permitted. Class 2 marking material is intended for use in preparation of temporary identification and instruction markers in shipment and storage of supplies and equipment as provided in MIL-STD-129. An important characteristic of class 2 material; e.g., in marking of vehicles during shipment and storage, is that it is readily removable even after extended weathering. These materials are not intended to be used on surfaces which become heated above 150°F. For exterior markers of the United States Air Force aircraft, the applicable material is covered by MIL-P-38477.