To convert it into a rechargeable light, you actually have to change quite a bit. Silkiechicken's is rechargeable because... well... I funded it
You'd have to get a battery charger, two (or 4 batteries to have two in the light and two spare), and a new lamp because the battery voltage will be higher and the lamp would blow out. If you don't think you'll use the light that much, it isn't worth it. But for people like Silkiechicken and I who carry our flashlights at all times and use them when they would make the least bit of difference, then it saves us money.

You'd have to get a battery charger, two (or 4 batteries to have two in the light and two spare), and a new lamp because the battery voltage will be higher and the lamp would blow out. If you don't think you'll use the light that much, it isn't worth it. But for people like Silkiechicken and I who carry our flashlights at all times and use them when they would make the least bit of difference, then it saves us money.