Nite IzeLRB2-07-PR LED Upgrade C/D Flashlights, 55 Lumen Bulb, Nylon/A

Q: will this work with 18v flashlight

This works on flashlights with 2 to 6 cells or 3 to 9 volts. 18 volts is twice its rating.

Q: Does this replacement lamp works with Maglite (old ones with normal bulb) that has 2*D cell. Kindly confirm at the earliest in order to proceed

I used one to update my older 2 D cell Maglight and it was easy to install and worked great.

Q: Does the brightness change with the number of cells driving this bulb, or will it put out 55 lumens at any voltage?

The incoming voltage is converted to a regulated voltage for the LED driver thus the output (55 lumens or so) will remain constant regardless of the incoming voltage (number of cells).

Q: does anyone know how this compares in efficiency (lumens per watt) to the 74-lumen version?

We rate our C/D cell LED bulbs based on ANSI/PLATO FL1 standards for lumen output and run-times. However, The LRB2-PR is 55 lumens, approximately 1/2W @ 4.5v. Run-time is 81 hours.LRB2-PRHP is 74 lumens, approximately 1W @4.5v. Run-time is 45 hours.