Intro to Special Wrench and Socket Terms and Features

In yesterday’s post about the wrench and socket recommendations for homeowners, I used a couple of terms that need to be better defined.

What is a crowfoot wrench? What does a ratcheting wrench’s Cap Stop feature do? What does an elbow ratcheting wrench look like? What does zero offset mean? Hopefully this post answers these and any other questions you might have had after reading that post and the many excellent reader comments. Plus, there are intros to a few more tools that you might find helpful.

If I left anything out, or you’d like to see other types of wrenches and sockets discussed, please help out or let me know with a comment!

Pass-Thru Sockets

Pass-thru sockets allow for long bolts and threaded rod to pass completely through them. This allows access in some places where even deep sockets aren’t long enough, but there’s a downside. Pass-thru sockets must be used with compatible ratchets and accessories, and while there are adapters that allow them to be used with traditional drive tools and accessories, that’s not always easy.

Craftsman’s Max Axess socket set is a good place to look if this kind of setup piques your interest.

Crowfoot Wrench

Crowfoot wrenches are open-end sockets that come in handy when reaching around obstacles. They work where common 6pt and 12pt sockets and wrenches simply cannot fit.

I have had good experiences with my set of Craftsman inch crowfoot wrenches, but would probably buy a Tekton set ($15/set via Amazon) if I ever need metric.

These are specialty sockets that you will either use all the time, or very rarely. They often come out when there’s no other way to access a fastener.

The crowfoot wrench above is shown attached to a ratchet with a short extension for extra reach.

Zero Offset Wrenches

Reversible ratcheting wrenches, like regular combination wrenches, often have 15° offsets. That is, if a wrench is resting flat on a table, the box end will point up at a slight angle of 15°. Flip the wrench over, and the box end will point downwards at an angle of 15°. A zero-offset wrench, which must usually be flipped to switch box end ratcheting directions, is completely flat with zero offset.

Combination wrenches and reversible ratcheting wrenches have offset box ends to help users reach over or around obstacles and obstructions. It also helps you keep a firmer grip on a wrench when the socket is in the middle of a large flat surface. With zero offset wrenches, you would not be able to grip the wrench and turn the fastener at the same time, at least not without a high risk of skinned knuckles.

Engraved vs. Etched Markings

Engraved = socket sizes are pressed or cut out the socket’s side.

Etched = laser etching is used to create a colored (often gold) marking on the surface of the socket.

Good etched markings are easier to read than bad engraved markings, but good engraved markings can be clearer to read and more durable than etched markings. It comes down to preference.

Cap-Stop Box Ends

Regular wrench box ends allow a nut or bolt head to go completely through. This can lead to slippage, where the wrench can move past the fastener. Gearwrench’s cap-stop feature has a thin metal lip on the top of the box end that does not allow nuts and bolts to pass through. If you have a nut on threaded rod, the cap-stop box end will not go past the fastener. This can be good, or bad, depending on the situation and user preferences.

In the photo shown here, the reversible ratcheting wrenches on the left are built with Gearwrench’s Cap Stop feature, and the zero offset wrenches on the right have ordinary ratcheting box end geometries. It is not possible for zero offset or other non-reversible ratcheting wrenches to have the Cap Stop feature, as this would prevent the wrenches from working in both directions.

Specialty Ratcheting Wrenches

There are a number of specialty ratcheting wrench styles. Here’s a brief rundown of the most common.

Flex-Head

There are locking and non-locking flex-head wrenches that help to reach fasteners in tight or difficult positions. Shown above are Gearwrench non-locking and non-reversible flex-head ratcheting wrench.

Flex-head ratcheting wrenches often have ordinary open ends.

Ratcheting Open End

Some ratcheting wrenches have ratcheting mechanisms built into their open ends as well.

Indexing/Elbow

Indexing, or ratcheting elbow wrenches, help to reach around obstacles. The pivot can be locked or unlocked, depending on how you want to use the wrench. In the locked position it can be swung like other ratcheting wrenches, and in the unlocked position it can work fasteners with a push-pull type of motion.

I reviewed Craftsman’s elbow ratcheting wrenches, and while they were neat, I haven’t missed them at all in the years since I gave them away.

Ratcheting Flare Nut Wrench

Flare nuts and fittings require special care to avoid damage. Ratcheting flare nut wrenches, like this Proto wrench, speed up tightening and loosening applications but are specially designed to provide a strong grip without marring softer metals or damaging corners.

Gearwrench came out with ratcheting flare/line wrenches a few years ago, but user reviews that I’ve seen have been mixed and lukewarm at best.

Deep Offset Wrench

Deep offset wrenches are double box end wrenches with angled and offset ends. Each end will often be a different size. Deep offset wrenches are typically used for reaching over or around obstructions to reach fasteners.

I bought sets of fractional and metric deep offset wrenches a few years ago, and they’ve come in handy. A few times they were the only tools I could easily use to reach a fastener. Other times, different tools or approaches could have been used, but a deep offset wrench saved time.

Read More: A Deep Offset Wrench Saved the Day!

Angled Socket Wrench

Angled socket wrenches are short double socket-end wrenches with a right angle bend at one end. Sometimes one end will be 6pt and the other 12pt, sometimes both will be 6pt.

The Facom fractional angled wrenches I own and love using have an opening in the bend that allows long bolts and threaded rod to pass right through. You can buy your own through Amazon, the Ultimate Garage, or other Facom dealers.

These wrenches are great for low-torque applications, and are a cross between box end wrenches and sockets. They’re not a must-have, but are nice to use for certain applications. I started off with one size and now have three (3/8″, 7/16″, 1/2″).

Sections: Sockets & Drive Tools, Tool Guide, Wrenches Tags: Ratcheting Wrenches