I thought I was pretty clever: I had taken a regular old pickup truck cap, insulated it, attached bug screens to the windows, and built a lightweight camper for my cross-country drive. But when I arrived out west, folks didn’t blink at my “camper shell.” Both phrases, “camper shell” and “pickup truck cap,” are popular–in different parts of the country. Though they sound like totally different accessories, they may refer to the exact same thing.

What is a pickup truck cap?

I grew up (in Vermont), where we refer to an aftermarket “canopy” or “topper” for a pickup bed as a “truck cap.” And we’re not alone: the phrase has about 27k monthly Google searches.

When northeasterners say “truck cap,” we mean the aftermarket fiberglass shells that fit onto your truck’s bed. They have a fold-down rear window designed to seal against your tailgate. To access your bed, you unlock and hinge up this window; then you drop your tailgate.

Why do we put caps on our trucks? In the Northeast, we get a lot of snow. And shoveling out your truck bed every storm is a pain. If you forget to do it, that snow can harden into ice you’ll be dealing with for the rest of the winter. Not cool.

In addition, a truck cap locks. It does have a rear window that isn’t hard to break. But your tools are a bit more secure in a pickup truck cap than just tossed in the bed of your truck.

What is a camper shell?

Many folks in the western or southern parts of the country refer to a pickup truck cap as a camper shell. In fact, the term gets 33k searches every month. Why? Because in those climates, an uninsulated truck cap makes a comfortable, dry camping spot during most of the year.

I always wondered why most of the truck caps available in the northeast have side windows. Obviously, the front and the rear of the cap need windows so you can use your rearview mirror. And it is actually legal to ride in a truck bed in most states. But certainly, the engineers at Leer aren’t going to all that work for the occasional passenger’s comfort.

I sent a picture of a pickup truck with a regular old cap around to all the writers at MotorBiscuit with one question: “What do you call the accessory on the back of this truck?” The answers were nearly 50/50. Our writers from Texas or other parts of the South agreed that it is a camper shell. Us northeasterners and midwesterners all said pickup truck cap. And in my experience, the Pacific Northwest and much of California sides with Texas for once and call it a camper shell.

What do the manufacturers say? Leer, which builds truck caps, only refers to its products as “caps.” But California-based “American Camper Shells” is a Leer distributor that refers to the same products as “camper shells.”

It looks like a camper shell and a pickup truck cap are the exact same thing!

Can you camp in a pickup truck cap?

When I modified a pickup truck cap for a fall cross-country drive, I figured it would need insulation. But in much of the country, for much of the year, an uninsulated pickup truck cap makes a great camper shell.

A regular pickup truck cap is waterproof, lockable, and has windows on all four sides. If you have a bunch of gear, moving it into the cab or the ground so you have room to sleep is a pain. But you can always do what I did and build a raised bunk with storage beneath.

If your pickup truck cap has no screens on its windows, you’ll want some mosquito netting. It sucks to choose between being able to breathe and getting bitten. But otherwise, if you have a warm enough sleeping bag for the weather, you should be all set.

Next, find out whether sleeping in your car is illegal, or see all the benefits of a camper shell in the video below: