A long narrow brush for the gaps a vacuum nozzle cannot enter: the duct behind a dryer, the condenser coil under a refrigerator, the channel between a cooker and a cabinet, the slot beneath a radiator. The shaft bends to follow a curve, so the bristles stay in contact with the surface the whole way along.
Polished wooden grip, steady in the hand through repeated scrubbing
Slender flexible shaft for narrow ducts and deep gaps
Small hole in the tail of the handle for hanging storage after use
Draw it through in one direction, wipe the lint off the bristles with a cloth, and hang it back up.
