Mag Lite, 3 D cell

Mag Lite, 3 D cell, retail $ Around twenty dollars
Manufactured by Mag Instruments (
Last updated 02-21-07


Just about everybody knows what this is. Mag-Lite has long been known for making sturdy metal, adjustable beam flashlights, and they're under millions of sinks, in car gloveboxes, garages, toolboxes, and sheds. This is their popular 3 D cell model, and is commonly available from stores like Fred Meyer and K-mart for around twenty bucks.

Mag Lites are sometimes sold with batteries, and always come with two bulbs.
This sample came without batteries, so I had to buy some seperately before I could use it.

Once you install batteries, the light itself is easy to use. Just push the rubberized button on the barrel to turn it on, and push it again to turn it off. The beam can be adjusted from a tight spot to a wide flood by turning the head one way or the other.

To change the batteries, unscrew the tailcap until it comes off. Tip out the old batteries (if any), and then slip in three new ones, positive (+) end first. Don't hold the light vertically and drop them in because that can damage the switch. Rather, hold the light horizontally and slide them in. This way, they won't smack into the switch contact with any real force.

With all the batteries in place, screw the tailcap on. The spring will have substantial tension on it, so don't be afraid to push on the end while turning until you catch the threads. Then tighten it until it stops.

Because the Mag Lite is an incandescent flashlight, sooner or later the bulb will pop. But fear not, because a spare bulb is located in the tailcap underneath the spring; enclosed in a protective foam sleeve. Pull the spring off the tailcap and pull the foam thingie out. Carefully remove the spare bulb. Put the foam back in place, press the spring back on, and reinstall the tailcap. Don't forget to pick up another spare bulb the next time you go to the store so you won't be caught with your pants down sometime later. :-O

But now you just want that bulb replaced. With the bulb lying nearby, unscrew & remove the flashlight head. The lamp is held in its socket with a metal collar, so unscrew this as well. Remove the old bulb and stomp on it. (love to hear them pop!) :)
Reverse the steps to reassemble your light. That is, place the new bulb in the socket, lower the metal collar over it & screw it down, then screw the head back on until it stops. Now you can turn your Mag on and adjust the beam to your desired focus, and use it to sweep up the old bulb.
(You didn't think I was just going to let you leave broken glass and flattened light bulb bases everywhere, did you?) ;-)

For years, Mag Lites have been known to be among the most durable of all commonly available flashlights. They're made of aluminum, and are sealed with O-rings throughout. You can use them as a hammer in an emergency.

Though Mag Lites aren't rated as being submersible, they are water resistant and should survive accidental falls into shallow water just fine if you pick them out of the water right away.


Mag-Lite at various focus settings.
All pictures taken with the light 3 feet from the wall.
Pictures deliberately underexposed to show beam details.

ProMetric analysis
Beam cross-sectional analysis.
Narrow beam.

ProMetric analysis
Beam cross-sectional analysis.
Wide beam.
Image made using the ProMetric System by Radiant Imaging.

One handy feature the Mag Lite has is that you can remove the head & reflector entirely and use it like a candle. The bulb will stay securely in place without the reflector. Larger Mag Lites like this may be a bit susceptible to being knocked over when stood on the tail, but if you stand it up somewhere where it won't get bumped, you'll be fine.


Durable and tough
Adjustable beam
Can be used as a candle
Can be used as a weapon
Reasonably bright

Quite heavy and large
Bulb often breaks when flashlight is dropped.
Switch rubber can sometimes pop out and become lost

    MANUFACTURER: Mag Instruments
    PRODUCT TYPE: Large handheld flashlight
    LAMP TYPE: Incandescent bulb
    No. OF LAMPS: 1
    BEAM TYPE: Adjustable, from spot to flood
    SWITCH TYPE: Rubber-covered pushbutton on/off on barrel
    CASE MATERIAL: Aluminum
    BEZEL: Metal; bulb & reflector protected by plastic window
    BATTERY: 3xD cells
    ACCESSORIES: Spare bulb
    WARRANTY: Lifetime


    Star Rating

Mag Lite, 3 D cell * WWW.MAGLITE.COM

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