Every deore lever i had, have developed leak from dirt getting in lever seals because theres literally nothing stopping it to. This is just 1 minute invention on top of full lever overhaul and beakefluid change. Have had couple of crashes where levers are dipped in dirt but almost none of it have gone past this rubber cover. Its not really dirt proof or anything, more like labyrinth seal that lets everything out rather than in.
by Budget-Engineer-7394