This sale is for BOTH bottles – a 2oz sprayer & an 8oz refill bottle, in the same package.
Using activator with CA is a convenience (you use it to set the glue almost instantly) but its very important to use it when working with Foam, since CA will often fail to cure without it. CA needs hydrogen ions (present in moisture in the air or on surfaces) and Foam is a synthetic product that doesn’t contain moisture. That is the reason why Foam-Safe CA takes much longer to cure on foam than it does with other items like balsa.
Use the 8oz bottle to refill the smaller one. This activator is 100% foam-safe and works with all kinds of CA. The main component is Heptane which is a mild solvent, and can be used to clean surfaces before applying CA.
Heptane is highly volatile and will evaporate from the spray bottle over time. Keep capped in storage and keep the activator away from your CA products.