250w hps/mh ballast ?

hello.
i have a local shop here that sells a 250w hps/mh ballast, without the need for different wiring each time, just screw the bulb u want and that's it.
they also have a one like this for 150w, but not for 400w or 600w.
so to my question, is a 250w hps/mh ballast like this is safe ? or it's just something homemade that they wired in the store ?

thank you :jointsmile:

Most new ballasts are switchable from MH to HPS. Digital ballasts do it automaticly. Magnetic ballasts have a switch.

(You have to change the bulb, first...:)...)

alrighty then :D
thank you.