I have a 6 year Old Dorcy Reactor LED Flashlight, The SST-90 LED looks like it will fit right in place of the existing unknown wattage LED. I think its a 1w LED, It gets 3.2v on new D size batteries. Not sure witch one I ordered, He said it was a 4.2v SST-90, But it maybe a 3.7v. I should get it in the mail in like 3 or 4 weeks due to the back to back holidays. I mite need to replace that 28 Gauge wire with 18 Gauge wire so it will handle the 9A of current coming straight from the Power on switch 9,000mAh D size batteries on eBay. For now The SST-90 would run at a lower voltage. But I mite get away with just upgrading the Old LED. Im not going to get the 2,250 lumens that the 30w LED SST-90 is rated at, Probably more like 1,000 lumens.