Medals involve not only the metal itself but also the ribbon, and these materials are susceptible to damage from moisture, dust, sunlight, and changes in temperature. Museums keep medals in locations with regulated temperature, humidity, and light levels to minimize discoloration and deterioration. At home, collectors should keep medals clean and dry, and should store them in a location that is not prone to extreme temperatures. Damp conditions corrode the metals and rot the ribbons, while high temperatures make ribbons go brittle. Acid-free cardboard boxes are a good storage solution, but wooden boxes coated with polyurethane resin are also acceptable. Collectors should avoid polishing medals, as the polish causes abrasion, and they should always wear gloves when handling the medals.
One of these multipurpose designs was the 'sawback' bayonet, which incorporated saw teeth on the spine of the blade.  The sawback bayonet was intended for use as a general-purpose utility tool as well as a weapon; the teeth were meant to facilitate the cutting of wood for various defensive works such as barbed-wire posts, as well as for butchering livestock.     It was initially adopted by the German states in 1865; until the middle of WWI approximately 5% of every bayonet style was complemented with a sawback version, countries such as Belgium in 1868, Great Britain in 1869 and Switzerland in 1878; (the latter introduced their last model in 1914).      The original sawback bayonets were typically of the heavy sword-type, they were issued to engineers, with to some extent the bayonet aspect being secondary to the "tool" aspect. Later German sawbacks were more of a rank indicator than a functional saw. The sawback proved relatively ineffective as a cutting tool, and was soon outmoded by improvements in military logistics and transportation; most nations dropped the sawback feature by 1900.  The German army discontinued use of the sawback bayonet in 1917 after protests that the serrated blade caused unnecessarily severe wounds when used as a fixed bayonet.