the switch stop work in my Mini Maglite AA . I buy a replacement switch over the internet and fix it , and then I find out that Mag Instruments would have send I a new one free under the lifetime warranty . too bad . the problem be that the light turn on erratically if at all , and do not focus properly . if you open the top , you 'll see that the bulb be stick into a washer-like receptacle which they call the Upper Insulator Receptacle . it be print `` do not remove . '' if you remove it , by prying it up with you thumbnail or a pocket knife , you 'll see the switch assembly underneath , with a triangular-shaped sheet metal slide contact . remember how the slide contact go , because it be likely to fall out . if you remove the battery , you can take out the lower insulator too . that slide contact be what fail on I . instead of be flat , the radial arm be bent . I think that if I have flatten it out with needle-nosed pliers , that would have fix it , at least for a while . anyway , the `` switch Repair kit '' come with the most idiot-proof detailed illustrated step-by-step instruction that I have ever see for any piece of equipment . they even give you a plastic `` tool '' to insert and remove the switch , if you be the kind of person who have trouble tap a flashlight onto a table without lose part , or you do not have a pencil lie around the house .