What is the difference between type 1 and type 2 on the knock off eBay drop checkers? It looks like the "bottom" bell is a different shape. Is it just an asthetic thing or is there a functional difference between the two? There is about $2 difference between them.
Also, I just noticed they have a different style yet. Look at this
eBay: NEW!! Co2 Drop Checker-monitoring proper dosage of CO2 (item 250039658709 end time Oct-23-06 08:45:25 PDT)