Although square and triangular drives appeared around 40 years earlier, it was William G. Allen’s hex drive, introduced in 1909, that became popular. Today, Allen fasteners are found everywhere—from circuit boards to cruise liners. Given their widespread use, it’s no surprise that the Allen wrench itself comes in a variety of forms. From handheld models to those for use in power drills and impact drivers, the options are plentiful.
This guide will take a look at the variety of features and functions to consider when choosing an Allen wrench set. Then, you can check out some of the top products on the market today to help you select the best Allen wrench set for your tool box.
- BEST OVERALL: TEKTON Ball End Hex Key Wrench Set, 26-Piece
- RUNNER-UP: Wera 05073593001 950 Spkl/9 Sm N Multicolor L-Key Set
- BEST BANG FOR THE BUCK: EKLIND 10111 Hex-L Key allen wrench – 11pc set
- UPGRADE PICK: Powerbuilt 8 Pc Metric T-Handle Hex Allen Key Wrench
- BEST T-HANDLE: Bondhus 13390 Set of 10 Hex T-handles w/Stand
- BEST FOLDING: Stanley STHT71839 Folding Metric and Sae Hex Keys
- BEST HEAVY-DUTY: Sunex 2637, 1/2″ Drive Master Impact Hex Driver Set
What to Consider When Choosing the Best Allen Wrench Set
Whether you’re an amateur or a professional, sooner or later an Allen wrench set is likely to be a necessity. In fact, almost every home tool kit for DIY incorporates one. The following features are crucial to consider when choosing the best Allen wrench set for your needs.
Most wrenches are designed to clamp around the outside of a hexagonal nut or bolt. By contrast, an Allen wrench fits inside a hexagonal recess. This type of wrench is primarily used for machine screws and bolts (rather than in wood) that fit into a threaded (blind) hole or often through a plate or clamp into a captive nut.
Because the Allen wrench fits inside the fixing rather than outside, it is especially useful in confined spaces where a standard wrench, or even a socket, would not be able to reach. Allen head fixings also allow for the application of greater torque than is possible with either slotted or Phillips screw heads. This makes an Allen wrench particularly effective with large fixings that require a lot of force to secure.
The base material for the majority of Allen wrenches is carbon steel, which has the inherent strength required to handle the twisting pressure (torque) involved in fastening or unfastening a range of Allen screws and bolts. Manufacturers can also add nickel or black oxide coatings to resist rust.
Some Allen wrenches are made of chrome vanadium or chrome-molybdenum (often called chrome-moly) steels. Chrome vanadium steel is very hard, with a degree of ductility. It will give a little without fracturing, and the chrome element prevents rust. Chrome-molybdenum has similar properties and higher tensile strength (resistance to shearing or deformation), which makes it popular in heavy-duty applications.
Chamfered vs. Non-chamfered
The basic form of an Allen wrench is either a hexagonal bar or a round bar that is shaped like a hexagon on the end. It is then bent into the common L-shape or has a T-handle attached. On budget tools, the hexagonal end is left flat.
There’s nothing wrong with this style, but it can be tricky to locate the wrench in the recess on the fixing. Additionally, frequent use can cause wear to either the wrench end or the fastener, exacerbating the situation. Better-quality Allen wrenches feature a small chamfer. This addition might not look like much, but it makes a considerable difference in quickly locating the wrench.
A ball-end Allen wrench takes this benefit a step further. It not only aids location but also means you can apply a degree of pressure at an angle, which is beneficial when screws or nuts are awkward to access.
Standard Allen wrenches are usually between 1 and 4 inches in length, so you can comfortably hold them in your hand, normally applying pressure with two or three fingers. Folding Allen wrenches are often shorter to be as compact as possible. Though you might lose some leverage, the thick body offers a firm hold.
T-handled models are typically much longer. Twisting these wrenches can apply tremendous torque, but it may not be possible to squeeze them into tight spaces. Depending on the application, you might want to purchase more than one set of Allen wrenches. Fortunately, most sets are affordable.
If you have several wrench sets in your arsenal, it’s often helpful to purchase a separate wrench organizer to give your tool box some structure. Luckily, most Allen wrench sets include some form of an organizer.
Low-cost Allen wrenches are often attached much like a set of keys on a keyring. Unfortunately, this isn’t as practical as it seems, and the connecting wires can easily become stretched or detached. Plastic clip-on racks are the most popular option, often marked with sizes for easy identification. T-handled Allen wrenches frequently include their own stand, which is great for bench use but too bulky for most tool boxes.
Two measuring systems are in common use today: SAE (Society of Automotive Engineers) is the inch system, also known as imperial, while the metric system is usually found on imported goods from Europe and Asia.
While equivalents are often provided, small differences in actual fastener size mean SAE and metric Allen wrenches are not interchangeable. Trying to force them will result in damage. Plan to either purchase the correct system for most of your needs, or invest in an Allen wrench set that includes both SAE and metric wrenches.
The number of Allen wrenches in a set varies considerably. Sets seldom contain fewer than eight wrenches, and these usually cover common sizes. However, sets that offer both SAE and metric sizes can include 20 or more wrenches.
Our Top Picks
Now it’s time to apply knowledge of the abovementioned features to selecting an Allen wrench set. Read on to discover our recommendations in a variety of categories for some of the best Allen wrench sets to add to your toolbox.
The Tekton Allen wrench set is among the most comprehensive on the market; it is a 26-piece set that includes 13 SAE tools and 13 metric tools. The classic “L” shape features small chamfers on one end to aid location, and the ball ends add to their flexibility. Each wrench in this set boasts a corrosion-resistant black oxide finish.
Some Allen wrench housing can be very loose. However, the hinged housing for these wrenches securely holds the tools when not in use and then opens flat for easy access. Each housing unit is a different color and marked with the individual wrench sizes for instant identification of the measurement system. Overall, this Allen wrench set is well made, presented in an easy-to-use manner, and very affordable.
Each of the 11 metric Allen wrenches in this set from Wera features its own color-coded sleeve marked with the size, providing rapid identification and increased hand comfort, particularly on cold days. Should the print eventually wear off, the size is also laser engraved on the wrench.
The Hex-Plus design of these wrenches is a unique shape intended to provide better engagement and reduced wear. A multilayered black laser coating prevents rust and is highly resistant to chipping or abrasion. This Allen wrench set does require a greater investment than many competitor products, but the precision and durability are outstanding.
This 11-piece SAE Allen wrench set from Eklind proves it’s possible to achieve quality on the smallest of budgets. These durable, US-made tools are crafted with heat-treated and tempered steel, providing both the required hardness for long service life and a degree of flex to resist snapping.
Each wrench is finished with a rust-resistant coating and complies with the standards of both the American Society of Mechanical Engineers (ASME) and the American National Standards Institute (ANSI). The housing is marked with each individual wrench size to allow for quick and easy identification.
These small Allen wrenches are an excellent choice for just about any standard tool kit, with a range of sizes that fit common fasteners on self-assembly furniture, electrical devices, bicycles, lawn mowers, and more.
Most Allen wrench sets are either the classic L-shape or have a T-shaped handle. These Powerbuilt Allen wrenches boast a sliding handle that can operate in either style, maximizing grip or torque as the application demands.
A speed sleeve also allows the user to firmly grip the shaft while still freely spinning the handle for rapid fastening or unfastening. This extended reach makes this set a popular choice with automotive and motorcycle engineers.
These wrenches are made of tough chrome vanadium steel, one of the optimum materials for these tools. The eight-piece metric set is housed in a smart, stable rack that holds them upright for quick identification and easy selection.
Bondhus crafts this Allen wrench set using its proprietary alloy steel called Protanium—and then coats each tool in its proprietary ProGuard rust-resistant finish for extra resiliency.
The welded T-shaped construction of each wrench is encased in a thick cushioned grip that is ergonomically designed to minimize the pressure on the user’s hands. This allows for all-day use with little chance of discomfort or cramping, which can be an issue with less user-friendly tools.
The set comprises 10 SAE Allen wrenches in a molded stand for bench use or wall mounting. Given its heavy-duty nature, this set offers a terrific value.
This Allen wrench set from Stanley includes nine SAE tools and eight metric tools, each clearly marked for size and all complying with ANSI specifications. The tough composite body features rubber inserts for a secure grip. Should the wrenches start to work loose over time, users can simply tighten the sides to restore the proper action.
The inexpensive nature of this set makes it ideal for adding to a home or professional tool kit or stowing in an RV or trailer.
The majority of Allen wrenches are made for hand use, but that means there’s a limit to the amount of torque that can be brought to bear. In heavy-duty industrial and engineering situations, that might not be enough. The solution is a set of Allen wrenches that will fit an impact wrench.
These wrenches from Sunex Tools feature a ½-inch drive found on high-performance models. The set includes 20 wrenches: 10 SAE tools and 10 metric tools. Each wrench is one solid, single piece of chrome-moly steel, ensuring it can withstand extreme demands while complying with ANSI standards.
Size markings are laser etched onto each wrench so they can’t wear off. A heavy-duty storage case allows for convenient transport.
FAQs About Allen Wrench Sets
This guide is designed to provide a thorough understanding of the key features to consider when choosing the best Allen wrench set for a particular range of tasks. While comprehensive in nature, you may still have a few questions. Check out some of the most frequently asked questions about Allen wrenches below.
Q. Are HEX keys the same as Allen wrenches?
Yes. Strictly speaking, the Allen name is owned by the Apex Tools Group, but, in general, the terms “hex key,” “Allen key,” “hex wrench,” and “Allen wrench” all describe the same type of tool.
Q. What is an Allen wrench with a hole in the middle?
The hole in the middle of an Allen wrench fits tamper-resistant hex screws that are usually designed to prevent unauthorized access to sensitive parts of equipment. You can still use this tool as an ordinary Allen wrench.
Q. How do you use an Allen wrench?
All Allen wrenches are used the same way, by inserting the hexagonal end of the bar into the relevant screw or bolt, then turning it to tighten or loosen. T-handled models generally allow the application of greater force and/or have greater reach. Ball-ended Allen wrenches can be used at an angle if access is difficult.