Duck® Fresh Discs have a gel based formula that self-sticks to the toilet bowl without germy cages. Duck Fresh Discs prevent the build up of limescale and stains that harbor germs. Just stick it to the inside rim of the toilet bowl so you can keep things clean. This is a refill pack with 12 discs, 2 x 36 ml. Remember to save the handle from the starter kit. Fresh Marine fragrance.