Q1: Metal Halide Lamp is not included in all Damsel lighting fixture. Can you recommend?
Ans 1: As long as the lamp is suitable for 150W RX7s lamp holder and comes with UV protection, it can be used as Damsel lighting fixture (150W type).
Here are some of the recommended brands that offers lamp for RX7s lamp holders:-
BLV (Signion series)
USHIO (Aqualite series)
OSRAM (Powerball series)
PHILIPS (MasterColour series)
Gisemann (MegaChrome series)
Delphis (Astro Beam series)
*Please check with the vendor that the model you chose comes with UV protection
Q2: Can I use my existing electronic ballast for the brands mentioned in “Ans 1″?
Ans 2: Please verify with your own vendor whether the light bulb is suitable for your existing electronic ballast.
Q3: Electronic ballast is not included in all Damsel lighting fixture. Can you recommend?
Ans 3: Depending on the watts of your existing lamp and the input voltage used in your country.
The easiest way is to check with your vendor whom you bought the metal halide lamp from.
Alternatively, you can check with the following electronic ballast maker:-
Osram, Philips, Vossloh-Schwabe, ELT, Luxcore