Our kits are thoroughly tested combinations of lamps and ballasts. They are designed to work with the number of lamps in each kit, not less or more. If you need more lamps, you just buy more kits. They scale perfectly linear. Our kits use only the most premium parts money can buy: Leviton brand lamp ends, SunHorse or Workhorse ultra-high frequency ballasts, engineered specifically for UV lamp, and have enough wire for most applications. And of course, they use only Solacure lamps, the leader is UV lamp design for UV curing, UV horticulture and materials aging. Prices are before shipping, which can be a little high due to the special packaging needed to ship ballasts and glass tubes together. In some cases, we will ship in multiple boxes to insure it arrives safely. If you have questions or need a special combination, then you should call Solacure at 1-800-600-8118, and a custom kit can be designed for you. Better yet, take a look yourself: www.Solacure.com