If you have a flip-flop hub on a fixed gear or single speed bike, and don’t use a cog or freewheel on the other side, Halo has a product for you. The Fix-T Cover fits over fixed or freewheel threads, to protect them from dirt and grime buildup. It’s a tiny little product you never knew you needed. The covers are simple CNC alloy parts and come in  blue, gold, green, black, red, silver, purple, and white, and weight in at 13 grams. They can be ordered from the distributor here for £4.99 each.