No transformer needed. The 3 Volt Lithium watch style battery can replaced (#HW2300) and each will last up to 80 hours. Plan them for a spot you can easily reach to flip the switch on and off.
LED Dollhouse Lights
LED Copper Large Glass Frosted Tulip Table Lamp
Reported Stock: 4
Vendor: Foltz MiniaturesModel: RB-HW2326
$24.96LED Globe Ceiling Lamp w/ Plastic Globe
Reported Stock: 2
Vendor: Foltz MiniaturesModel: RB-HW2337
$24.96LED 3-Arm Silver Frosted Down Tulip Shade Chandelier
Reported Stock: 4
Vendor: Handley House MiniaturesModel: HW2360
$57.95LED 5-Arm Frosted Down Tulip Shade Chandelier
Reported Stock: 7
Vendor: Handley House MiniaturesModel: HW2323
$79.95LED Ornate table Lamp w/ Plastic Fluted Shade
Reported Stock: 5
Vendor: Handley House MiniaturesModel: HW2303
$23.95LED Single Bulb Silver Lamp Base
Reported Stock: 7
Vendor: Handley House MiniaturesModel: HW2357
$15.95LED Clear Etched Ceiling Lamp
Reported Stock: 1
Vendor: Marys Dollhouse MiniaturesModel: OS-HW2339
$24.95