Bayroklar Duo Tabs. The size of this product is 2 x 4.5Kg. (ie 24 individual doses) Bayroklar Duo tabs (Bayrol) is a completely chlorine free swimming pool sanitizer for use primarily in indoor pools. Customers with skin conditions such as eczema have commented that their condition does not seem to be aggravated with this product, as with chlorine based sanitisation. Please use Superflock with this product to keep your pool sparkling clear. Always read and adhere to the instructions on the pack and never directly mix chemicals. Don't forget, the price you see is the price you pay not a penny more. We sell chemicals cheap, not cheap chemicals!