Keystone Ballasts 22 & 32 Watt or 32 & 40 Watt circline, 120V, w/sockets, ELECTRONIC model number KTEB-2C72-1-TP-WS-CP

I don't know much about ballasts except that this was to replace one that failed and it is identical in all respects which made installation simple. The light goes on, there is no hum, and it works better than the old one!

Perfect replacement ballast. Fit in the spot and worked without any tweaking. Definitely recommend.

Bought in hopes it would replace the round shaped ballast. Fits inside the smaller light, but I had to drill and put new screws as the shape was different. Works great, and only half the price of the exact replacement.

Function is good but mounting hole distance was not given from specification. I took out the old base plate to attached to this new one.

Great replacement ballast. Very easy to install

Have double tube circline lamp, purchased as a unit in 2001. Original ballast lasted until 2012 (11 years).I replaced the ballast with a GE Magnetic ballast (GEM1FC16T9RS120 Product code 89720), Magnetic Ballast (726VLHWSTCP) Rapid start, 120Volts 60 Hz. This was either a direct exact replacement, or very similar to original. The GE replacement ballast caused the circline bulbs to dim, initially slowly, at the end of the brief 3 year life the brightness approached that of a 40 watt incandescent light bulb (for both circline bulbs burning at the same time. First replacement ballast lasted until 2015 (3 years). I do not recommend the GE Magnetic ballast, it does not last very long.This Keystone electronic ballast is the second replacement. It makes the 2 cirlcline bulbs brighter than the sun - so bright that you may burn your eyeballs out if you look at it for too long. In other words, Keystone ballast works great. Actually I sort of wish it wasn't so bright/great: you can see every speck of dirt in the kitchen now.I will update this upon the demise of this electronic ballast, so you will know lifespan.

The original ballast that I was replacing hummed for 28 years and and would occasionally cut out if the light was left on for a few hours. I finally got fed up and looked for a replacement. My local Home Depot and Lowes does not stock a compatible replacement. The Keystone Ballasts KTEB-2C72-1-TP-WS-CP was available from Amazon and delivered the next day. Installation was simple. The device worked perfectly. Bonus, that hum for the last 28 years is gone. Excellent.

I would return this if i had not installed to our light fixture or if the mounting the light fixture to the ceiling is not a PIA.It will light up the bulbs but not instantly, it will have 1-2 seconds delay before the light bulbs fully get to the brightness that they supposed to be. I thought maybe the bulbs got problem, i changed the new set of bulbs and same thing happened.It works for what i need so i keep it. It is also barely fit to the circline light fixture because it is not in a square or circle form factor.