LSE Lighting (2-Pack) 602805 UV Replacement Lamps Compatible with Viqua Max C, D, D4 Systems – Trojan Sterilight Equivalent – High Performance UV-C Bulbs – Designed in USA

The BAD: We only received 1 when we should have received 2 but a replacement is being sent.The (very) GOOD: Contacting the manufacturer (Viqua) about our D4+ system which came with the (new) home we purchased, they insisted that ONLY their bulbs would work so we purchased one for nearly $200! Long story short we didn't want to pay that much in the future for a bulb that needed to be replaced every 10-12 months so we researched the heck out of compatible bulbs and manufacturers. Upon reading about LSE we decided that was the company to go with because that's what the company does. They manufacturer UV bulbs for industry. In fact I believe they actually manufacturer for Viqua! We got a TWO PACK for $65+tx. One single OEM Viqua bulb costs $150 at the minimum. So, for the price of one Viqua bulb we can get four LSE ones!How do they fit and work? The bulb(s) we received were individually wrapped and placed in a cardboard tube (1 per tube) and then in a padded box. They (it) arrived within a couple of days in perfect condition. The only minor issue, which has been pointed out in other reviews, is that you need to break off the two shortest tabs in order for the harness to fit which is no big deal to do. Just get pliers, grip at the bottom part of the tab and gently pull towards you. It snapped right off with zero damage. Once those were removed it fit perfectly and all the lights were green! It's the same exact everything (except those tabs) as the OEM bulb.I'm not sure why others give less than great reviews, maybe because they ordered the wrong bulb or didn't know enough to pull the tabs off. Now, Granted you shouldn't have to snap off tabs but that's worth the nearly $150 savings for something that works just like the OEM! As long as it says it fits your unit it will work.

Good product.

The first of the 2 bulbs in the pack fit and worked fine. The following year when I went to replace the bulb; I could not get the new bulb to fit after trying carefully for 30 minutes. I called the professional that originally installed the system to come change the bulb. He tried for 10 minutes and announced that something was wrong with the construction of the bulb; nothing that was obvious but just would not plug in properly. He had brought a new bulb and had it in place in 30 seconds. Chalk it up to poor quality control of this product. You get what you pay for.

It'll works but you have to break some plastic tabs off the side to get it to fit the D4.

These lamps worked fine. I ordered 4 of them on two different occasions. All 8 lamps worked no problem. LSE Lighting has another offer for these same lamps here on Amazon (single lamps- not a 2-pack like these). The plastic on those lamp heads was very poor quality and most of the lamps didn't work. These are made with better quality plastic and all lamps have worked. Be sure to order these and not the others!

Second time purchasing these lamps. The work and last the full year. Easy install the first time this order the taps would not allow the connector to seat a fraction to larger. I had shave some plastic off the tabs. Easy fix.

I‘ve purchased the single and the two lamps over three years. Both fit perfectly and lasted over a year; I replace every 365 days. I just ordered 2 more lamps on 9/10/21.

I have purchased these prior and they worked fine, this time the plug would not fit the pins on either bulb. It's too late to return them as I bought them before my old bulbs needed replacement. My advice, buy the brand name, or make sure and check them when you get them. As for me, never again.