I'm going to order the Taylor K-2006 test kit, but have been reading on this board (thanks everyone!) that I should probably purchase extra CYA reagent. I can't tell from Taylor's website which R-0013 component to order. There's R-0013A, R-0013C, etc.

Maybe it's different size bottles, but I can't tell from the Taylor website. Does anyone know what product number I should order?