In this video I upgrade an 18 volt Hitachi Flashlight with an LED bulb. This bulb would likely also work in 18 volt flashlights of other power tool brands. I also compare it to a newer Ryobi LED flashlight.
5W 6-24V P13.5S LED Bulb (eBay affiliate): https://www.rickmakes.com/5w_p13.5s_led_bulb
5W 6-24V P13.5S LED Bulb (Amazon Affiliate)
US: https://amzn.to/3e37uOi