(09/16/2007) - I bought this regulator/solenoid/needle valve combo based on the strong reccomendation of the previous reviewer. I have to say I'm very happy with it. The needle valve is very easy to adjust, and remains steady without issue. The solenoid has an orange light that indicates power. When the light is off, so is the solenoid. Highly reccomend this regulator set to anyone thinking about a calcium reactor. Save yourself money in the long run, but a good regulator/solenoid/needlevalve set the first time instead of buying cheap the first time....wish I had.

(09/08/2006) - I've gone through many CO2 regulators in the past and this unit is by far the best. Does not have a secondary pressure knob and is preset at approx 20 psi (This is a big plus). Only adjustment is the bubble rate. High quality needle valve- I can easily set the bubble rate down to around 1 bubble per 5 seconds and it holds it rock solid. If you're in the market for a CO2 regulator, my advice is to spend a little more and get a good a unit with a precision needle valve. Don't waste your money on a cheapo unit that you have to tweak every few days.