Leatherman invented the multi-tool, and the firm has been at the forefront of the development of this invaluable gadget ever since.

The company now offers a whole array of different products. Just about every imaginable accessory is available in a variety of sizes to suit all needs. Far from resting on its laurels, however, Leatherman continues to introduce tools that provide innovative solutions, ranging from those that make life just a little easier to those that can dramatically improve user safety.

We've recommended a few of our favorites, and in this shopping guide we look at your choices in more detail. It outlines the important features you need to look for and provides answers to common questions about Leatherman’s products.

A multi-tool for every demand

Leatherman produces four sizes of what we all recognize as a multi-tool: keychain, pocket, full, and heavy-duty. Each is fitted with anywhere from 6 to 21 tools, from scissors and bottle-openers to rulers and screwdrivers, and, of course, a wide variety of blades. Some are designed as all-rounders, others for particular trades, such as cable installers. There are also ultra-light Skeletools for those who need practical accessories but want to carry as little weight as possible.

Alongside these, there are pocket knives, safety equipment, pocket tools aimed at hunters, winter sports fans, and surfers, and even wearables – multi-tools you can carry on your wrist. All of them are made from high-quality materials and components to the most exacting standards.

Somewhere in the range there's a Leatherman multi-tool to suit practically every individual. It's not difficult to find something with an accessory list that reads like it was written specifically for you. There's a Leatherman for opening boxes or bottles that also includes a wrench and a screwdriver. Another can help you fix your skateboard.

Given the variety in the Leatherman lineup, it's important to think about the tools you need and the way you'll use them. It might be tempting to go for a heavy-duty model with every conceivable gadget, but if you need the tool for backpacking, there's a good chance that it will be heavier than you want to carry and have accessories you'll never use. Maybe something smaller, with a built-in lanyard point would be better. You'll probably save money, too. On the other hand, if you want that gift for the person who has everything, there are models with titanium handles and Damascus steel blades!

Here are a few features to think about as you shop:

• Geared drives allow you to apply more force than simple pinned connections.
• Sprung tools return to the open position with each use, giving a faster action.
• Locking tools provide user safety.
• Folding tools that extend out from the handle allow you to use them while the rest of the device is closed.
• Replaceable blades extend the life of your multi-tool. Wire cutters wear down eventually and it's not practical to resharpen them.
• Switchable blades give you the option to extend versatility beyond the tool's standard collection.
• Sheaths come in handy and there are many available. Leather looks great and has a quality feel, but nylon might be more practical, particularly if it will frequently get wet. MOLLE versions are especially tough and may have pockets for extra bits or other accessories.

Leatherman is undoubtedly the best-known name in multi-tools, and the company’s material choices and high production standards mean these tools are seldom cheap. You might be able to save money with another brand, but Leatherman remains popular because it offers unrivaled versatility, excellent performance, and tremendous durability.

Inexpensive: Pocket tools start at less than $10. Entry-level models in the keychain range, pocket knives, and the Z-Rex Firefighter tool cost a very affordable $30 and up.

Mid-range: The popular Rebar, an update on the original Leatherman, is about $70, and you have lots of choices in the $80 to $150 bracket.

Expensive: The specialized tactical MUT multi-tool is in the region of $240. At the top of the range is the amazing Tread Tempo multi-tool watch at $450.

• Sharpen the blades. All blades need sharpening eventually. Any straight-edged tool can be honed to an angle of 32° using whatever method you prefer. Serrated blades need a tool designed for the purpose (you might already have one, but they’re widely available). The angle should be 20°. Never sharpen the back of serrated blades because it will change the shape of the serration and reduce performance.
• Clean your multi-tool. If necessary, clean your tool in warm water with a little detergent. Difficult areas can be cleaned with mineral spirits. Never use strong chemicals like bleach, brake cleaner, or acetone because they can damage plastics. Saltwater marks or other surface stains can be removed with a nonabrasive metal polish.
• Lubricate your multi-tool. Oil it lightly with a spray lubricant such as WD-40. Linkages, gears, and other movement areas can be further protected with a Teflon lubricant or polytetrafluoroethylene (PTFE) grease.

The standard design of the Leatherman multi-tool is very well known, so we thought we'd take a quick look at a few of their other clever solutions. It's always worth having a tool like the Leatherman Z-Rex in your vehicle. It offers a sure grip and includes a carbide glass breaker, reversible strap cutter (with replaceable blades), and a driver for hex bits. For those who like to be prepared wherever they are, there's the remarkable Leatherman Tread Tempo, a stylish watch with a precision Swiss-made movement combined with a stainless steel strap that offers 30 different tools.

Q. Can I take my Leatherman on a commercial flight?
A. It's a common question, but unfortunately the answer is not straightforward. Any kind of bladed tool, and those with sharp points, would not be allowed in a carry-on. They're perfectly OK in your checked luggage, though.

Certain Leatherman tools are currently Transportation Security Administration (TSA) compliant, such as the the Hail (popular with skiers and snowboarders) and the Piranha 2 wrench and driver. However, rules can change at any time, so it's important to check before departure. Additionally, TSA agents have the right to make individual decisions on a case-by-case basis. While the Leatherman site should have up-to-date information, if the agent says no, that's end of story.

What could add even more complications are the rules at the point of entry or exit in another country. The TSA is responsible for the United States. While most other countries have similar restrictions, each is responsible for its own jurisdiction. What does and doesn't constitute “dangerous” can differ. It's possible that you could walk through US customs just fine but be stopped on arrival somewhere else. It's easiest just to put it in your checked luggage. It's not very likely you'll be adjusting your ski bindings on the plane anyway!

Q. Do Leatherman tools carry a lifetime warranty?
A. Actually, it's 25 years, which is still impressive. It doesn't cover sheaths, which are very durable but could be subject to high wear and tear. Leather and synthetic materials aren't as tough as steel. The warranty also doesn't cover some accessories. Basically, Leatherman is confident of each tool's quality, so if it breaks, the company will replace it.

Q. Can I change or replace individual blades or other devices in a Leatherman?
A. Some parts will eventually wear out – cutter blades or saws, for example – and many of these are replaceable. They should be available where you bought your Leatherman tool. Other small items might get lost, such as pop-out tweezers, and replacements are also available for these. However, you can't individually customize a tool. If it's damaged, you can return it to Leatherman for a replacement, but you can't, for example, substitute a blade for a wrench. This is because every component of the tool is designed to work together. Changing one could compromise this functionality.