In German the word “ersatz” is used to describe an inferior substitute item used only when the normal quality item is not available usually in time of need or war. Ersatz in the military usually means a replacement unit made up of partially trained new recruits, recovering wounded and older men generally considered to be of second string quality.
“Pioneers” are like engineers. The engineers do the planning and the pioneers carry out the engineered projects by doing the actual work.
The Second Bavarian Ersatz Pioneer Company was part of the First Royal Bavarian Mixed Ersatz Brigade which was one of three such brigades that comprised the Bavarian Ersatz Division in 1914. Verdun is among their many battle credits so the unit had a respectable combat history by 1917 and the bragging rights to go with it. As an ersatz unit they didn’t have the glorified history and regalia of the more established units which may explain the reason that the fob illustrated below was issued.
Often when a fob is encountered there is the question of whether the flat fob loop is really a medal that looks like a fob or if it really is a fob. In most cases one would have to know how the item was issued but in this case there is no doubt. With it’s massive weight this cast bronze item can only be a fob and as of 1917 that would have been the only way it could have been worn or carried legally. The design shows a soldier throwing a potato masher grenade with the inscription “1914-1917 2. BAYR. PIONIER ERS. K.” Interestingly the soldier is wearing his round cloth hat and not a helmet. The reverse is blank within a thick rim.