The only other assembly required for your Flowtron was inserting the octanol cartridge, which slides very easily in to the cartridge holder on the bottom of your device. The cartridge lasts about 30 times and prices about $fifteen for any replacement a few-pack. Through my testing, I looked at https://charlielotuz.blogs-service.com/59793879/the-5-second-trick-for-flowtron-bk-40d-electronic-insect-killer