2 Pack Replacement Bulb, 5W UV-C Bulb Compatible with Germ Guardian LB4000 AC4300BPTCA, AC4825, AC4850, AC4850PT, AC4900, AC4900CA, AC5300B, AC5350B, AC5350W Air Purifier

they work out of the box and fit perfectly.

This is a good ultraviolet replacement for a Bionaire fan.

These bulbs are a great replacement for my Germ Guardian air purifier. I handle them with gloves to keep body oil off the bulb & they last for nearly a year per bulb.

Work well but short life

Drop in perfectly where old ones were.

Exactly what I needed and great value. Joe

I purchased this product ( 4 bulbs), after I went through all the reviews to determine if it would work in my air purifier Bionaire BAP536UV-U. The description of these bulb did not indicate if these would work. I installed the bulb into air purifier using gloves, as fingerprint oils will shorten this lifecycle of the bulb and replacing protective metal cover (required or air cleaner will not work. I checked the product and LED on top of air cleaner stays lit and checked front grill by looking up in darkened room and the UV bulb indeed is lit. If it were not for going through the reviews of other purchasers; I would have not known the bulb would work. I will see if the bulb lasts as long as described. When I am not in the room where air purifier is used - I turn the bulb off and also will have bulb off when initially starting air cleaner up in high speed; to prolong the life of the bulb.

UPDATE! This month I cleaned the pond which uses these lamps to prevent algae. the former lamp had burned out - as they do from time to time. Bought these as standby lamps for when one burns out. Well, yesterday (Nov. 5) discovered the lamp was out. Installed a new bulb but nothing happened. It didn't light up. Tried a second lamp. It didn't light up. Tried a 3rd and the 4th. NONE OF THEM LIT UP. MY background: 7 years as a manufacturing engineer. 13 years as a quality engineer. I know a thing or two about electronics. These lamps have self starters internally that put two filaments in series with each other. They glow and get hot. When the electrons begin to flow from one filament to the other (not the series connection) the new pathway for electrons shuts the starter off and the bulb remains lit. I tested my ballast and found no issues. Tested the lamps and found all four of them were OPEN CIRCUIT's. They can't light if they're open circuit. Bought bad junk. Let's see if the seller honors either a refund or a replacement - WITH WORKING BULBS! Their website no longer exists and their phone number is disconnected. Made a quick buck and ran!

Not work but refund money