The headlamp that belongs in every go-bag

Quick answer: Buy a headlamp with a modest peak output, a long-running low mode, a red light and a lockout, powered by AAA batteries you can swap. Then put a fresh spare set in the bag and check it twice a year.

Picture 2 a.m. The power's out, something's wrong in the house or on the road, and you've got a flashlight in one hand and your daughter's hand in the other. Now you need to open a door, move a branch or unzip a bag. The flashlight goes in your teeth.

That's why the go-bag gets a headlamp. It puts the light where your eyes are and leaves both hands free for the job. Every bag in your house or truck should have one.

The one

You're buying a type, not a model. The spec profile:

• Peak output in the low hundreds of lumens. Around 200 to 400 handles walking, searching and working. More is a bragging number.
• A low mode that runs for many hours. This is the mode you'll live in. Read the runtime the maker lists for it, not for the top setting.
• A red light mode. It saves your night vision and doesn't blind the family sitting next to you.
• A lockout. It keeps the button from switching the lamp on inside a packed bag.
• A weather rating of at least IPX4. That's splash resistance. IPX7 means the maker rates it for brief submersion. Both are published ratings, so look for the number on the box or spec sheet.
• Standard AAA batteries, or a hybrid that takes AAAs or a rechargeable pack.
• Light weight. Under about four ounces with batteries means you'll actually carry it.
• A tilting head, a wide stretchy band and a button you can find with gloves on.

Petzl, Black Diamond and Princeton Tec all make headlamps in this category. Read each maker's spec sheet against the list above and you'll find several that fit.

Why this one

Hands free beats bright. Nearly every emergency task needs two hands: changing a tire, working a flat, holding a child, splinting something, finding the breaker box. A handheld light fights you the whole time.

Swappable batteries beat a built-in charge. A go-bag sits. A rechargeable-only lamp that's been in the closet for eight months may be at half charge or dead, and you can't borrow a charge from a gas station. A lamp that takes AAAs can be fed from a drawer, a neighbor or a store shelf. The hybrid design gets you both.

Low-mode runtime is the number that matters. Makers who follow the ANSI/PLATO FL1 standard publish runtime measured to the point where output drops to 10 percent of the starting level. That standard gives you a fair way to compare lamps. If a maker lists lumens and no runtime at all, treat the lumens with suspicion.

Red light earns its spot. You'll use it to read a map, check a kid's scraped knee or move around a camp without waking everybody.

If you want the bigger picture, a headlamp is one item in The Ten Essentials and Why Veterans Still Carry Them, and it's the one people most often leave home on a "quick day hike." Those hikes run long. Read The First Hour After You Realize You Are Lost and notice how many of the good decisions are easier with light on your hands.

What to skip

• 1,000 lumens and up. It's heavy, hot, hard on batteries and wasted in a go-bag. You're not lighting a stadium.
• Rechargeable-only models. They're fine for a nightly trail runner. They're a gamble in a bag that sits.
• App connections and fancy modes. Every extra mode is another press of the button while you're stressed. You want off, low, high and red.
• Cheap multipacks with no runtime figures. A price that looks great and a spec sheet that's missing details is a reason to keep walking. If the maker can't tell you how long low mode lasts, assume the answer isn't good.
• Alkaline batteries as your standing stock. They can leak when stored for long stretches, and a corroded battery compartment turns your light into a paperweight. Lithium AAAs are sold with a long shelf-life claim, so check the package. Cold weather is where they pull ahead too.

If your situation is different

You hike at night or run trails. Move up the output scale. A bigger beam with a bigger battery makes sense for moving fast on rough ground. Keep the cheaper go-bag lamp separate and don't raid one for the other.

You've got small kids. Buy lamps that fit small heads, not an adult band cinched to the last notch. A light that slides over a child's eyes won't get worn. Practice with them at home so the first night in the dark isn't the first time they've touched one.

You keep a kit in the truck. Heat and cold swing hard in a vehicle. Store the batteries in a zip bag beside the lamp, not inside it, and check the lamp seasonally. Our piece on turning your truck into an overland rig covers where a kit like this lives so you can find it fast.

You prefer rechargeable. That's fine if you commit to the habit. Top it off on a schedule you actually keep, and carry a small power bank in the same bag.

Before you buy

• Is there a published low-mode runtime, ideally to the FL1 standard?
• Does the spec sheet list an IPX rating, and is it at least IPX4?
• Does it have a lockout, or can you turn it off by reversing a battery?
• Will it run on plain AAAs, even if it also takes a rechargeable pack?
• Is there a red mode that doesn't take five presses to reach?
• Read the warranty document itself. Look at the length, what it covers and who pays shipping.
• Read the one-year-later owner reviews and look for complaints about the button, the hinge and the battery door.
• Pick a date, twice a year, to test every lamp in every bag. Replace the batteries. Pass the old ones to a flashlight you're not carrying. If a neighbor ever borrows yours, hand it back with fresh batteries in it.
• Check the current price.