Most already know that Firenock provided 2 types of battery, BR and BL I believe I have asked this before, but no real answer, thus a 2nd post after a year. I am seriously thinking of providing the 3rd type, BU. I would like to hear what you all have to say and should I do the 3rd kind, if so, what the price should be to be consider reasonable, I am thinking between $17.95 to $19.95 for that BU. Your opinion is very important and will dictate if I proceed with this or not! The BU battery in my opinion will satisfy those who wanted an ULTRA long shelf life and ULTRA reliable battery. The failure rate of this battery is about 1:100,000. So if the battery is dead, it is drained, or shorted the shelf life is easily. While the BR failure rate is about 5%, and BL is about 2%. BU batteries can be installed in Firenock and if you remove it our of the system and reinstall it every season, it is an easily 5 seasons battery. The fact remains, like all battery operated system, it will drain a little when it is connected, so even if you do not take the battery off the circuit, it still will last up to 3 years, unlike the BL or BR which is about 1 year! The down side, it does not go as low temperature as the BR, -4F max. It does have great upper limit on temperature. It also must be used with extreme shock end cap due to no groove for O-ring. Below is the capability matrix. Opinion and suggestion welcome.