When you install/use a 3-way lamp for the first time, the truck gets a lamp-to-lamp connection. Too tight and you may deform the bulb or break the bulb and the 3rd way won't work properly. Too loose and the bulb will not connect properly and the 3-way will not work. After a few times you will feel it and it will be easy! As for those particular bulbs - GE bulbs are great! When choosing a lamp you should pay attention to the lumen number, depending on how bright you want your lamp to be - the higher the lumen number should be. The lower the light, the lower the lumens #. We recommend these lamps and hope our review helped!