LONGER SERVICE bulb for Sundance spa hot water tub make from materials, and it will last for more than 9000 hours with minimal maintenance, safe and full of durability to use this SPA UV light bulb is, remove the screws, enclosure cover and gasket in place, and then slide the UV bulb back inside the quartzs tube (We suggest you to wear gloves before installing the bulb to skin oils on the glass xl replacement bulb 6472-841 for 2012+ Sundance spas, for hot water tub series J-200, J-300, J-400, J-LX, such as J245, J275, J315, J325, J335, J345, and so on PART NUMBER This spa replacement bulb is know as part numbers 6472-841 WARM PROMPT Due to the special welding technology, when you open the package, please grasp the lamp tube and take it out Try not to pull the connecting wire to avoid damage to the lamp wick