Backpacks are a crucial part of your gear when it comes to the outdoors. For this reason, when it’s time to buy one—whether as a replacement or as your first—it pays to ask yourself a few questions to ensure you get the right one. Below, you’ll find three key questions that anyone shopping for a backpack should consider before making a purchase.

How big of a backpack do I need?

When comparing packs, it’s important to make sure any potential product will hold enough gear for the longest trips you’ll be planning. To check the pack’s capacity, I suggest either bringing your own gear from home or using gear in the store to stuff it with. Try to use gear that you’d normally be carrying, such as tents or sleeping bags, if possible. Here, you’ll want to make sure it will hold the space your gear takes up, rather than the weight.

What features do I need?

This will really depend on what type of hiker you are. Minimalists will desire different extras than those hikers who are all about organization, so it’s smart to decide on what extra features you absolutely need and only consider backpacks that include them. Such features may include water bottle pockets, shove-it pockets, loops for tools or skis, or an extendable lid.

How do I tell if it fits?

In order to get a good idea of whether or not your potential pack is a good fit, first load it with some weight (at least 20 pounds for an accurate test). Then, tighten the hip belt, making sure the padding is centered just above your hipbones. Tighten the shoulder straps, sternum strap, and hip stabilizers, as well. Once this is done, you’ll want to check if the lumbar pad sits firmly in the small of your back. If not, you’ll either need to adjust the pack’s fit (if it offers this), or consider another one. Also, feel for any uncomfortable pressure points on your hips or gaps in the shoulder straps. If these can’t be fixed then you might want to look for a different pack.

Lightweight or heavy-duty?

Again, this will depend heavily on the type of packer you are. The amount of gear you carry can have an impact on your pack’s support, so consider that first. If your base weight is consistently low (below 15 pounds, for instance), then it’s probably okay to go with a lighter model. However, if you’re regularly pushing the 35 to 40-lb mark, then I’d suggest opting for a larger model with a more rigid suspension, in order to get the support you’ll need.

Stick to your guns when it comes to desired features, be realistic concerning your experience, and don’t be afraid to take a backpack for a test drive in the store before making a purchase. Implementing these concepts, as well as asking questions like the ones outlined above, will help ensure that you go home with the backpack that’s right for you.