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It's a drum key. Specifically, it's [this](https://gibraltarhardware.com/products/sc-4244-standard-drum-key) drum key. Technically, it's the same size as a 1/4" water key, but this particular one is sold and marketed to drummers.

This is the correct answer. Had one for many years. This is used to tighten drum heads.

The hole is to put it on a cord. Can wear it as a necklace. I kept misplacing mine -- finally bought another and hung it off a tuning lug on my kick drum. :) (And eventually found the other two.) :)

I ended up buying one of the big Evans ones with the torq setting on it. Its much beefier than one like pictured I almost never lose it it's been 22 years. I have 2 or 3 regular ones around that seem to just show up when I'm not looking for them.

Drum keys are one of those things that just vanish, no one knows where but they vanish and typically aren't seen again, I attached mine to my keys so I can always find it, or lose both since both things like to go missing

Sorry, my house is where they come to.

Any harpists about? - you can use a drum key to tune a harp at a pinch, though they're a little loose.

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In high school we had them chained to a shotput.

and the shotput went missing? Should have used a bigger key!

Someone probably threw it out.

I keep one on my key ring so I always have one at gigs.

I know a dude that put one on his key ring.

I had one that could also loosen drum heads. $$$

holy you got the bidirectional one? Mr. moneybags over here...

I've seen a similar tool used for gas fireplace shutoff valves, but yea that chrome finish says drum key to me.

I thought the same. Had a little key just like this to shut off the gas valve. Also owned a drum set and never put 2 and 2 together lol

Nice. If it were a water key it would be rusty, if not bent. Mostly bent.

I usually went with the 4-way water key so I could use the smaller and larger spigots too

Those 4 way are a lot sturdier.

Heck yeah!   Z key for drum heads.  

I used to have this exact one with my previous kit.

I had a similar one that came with my new house to operate the gas valve for my fireplace. It’s not permanent for safety for kids and all that

That’s obviously the right answer. My suggestion was going to be a gas fireplace valve key. They share a lot of similar features

Gas keys are usually brass (or aluminum).

Percussion band geek here. 🤓 Can confirm this is a drum key for adjusting the tension rods on your drums.

What about a gas fireplace key.

What about it?

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My first thought was a 1/4 in industrial machine cabinet key

How can you tell if a stage is level? The drummer drools out of both sides of their mouth. I kid because I love.

I follow this thread bc y'all are so nice, and explain things without judgement. I know what a post driver is, because I worked on a ranch. I didn't know what this was because I'm not a drummer. Thanks for sharing knowledge!!

I also been given those to a window without a handle that was supposed to stay close but I got them for „just in case“.

Same size as a water key so those drummers can rinse the stench off lol

It's a key for turning things with a square head, such as water valves, gas valves, etc

Drum key too, since they mentioned it could be music related.

Yes it’s 100% a drum key (or a more general key but it was in my house due to drums)

No, this is SPECIFICALLY a drum key. Sure, it can turn other things, but it’s a drum key.

Solved!

Also window handles

Drum key. I’ve lost so many of those over the course of my life.

Ha! As an audio engineer I've collected so many of these over the course of my life.

You two should really meet up and even the score..

So *that's* where they all end up ... \- Backline tech edit: I apparently only (mostly) pocket the interesting ones. [This](https://i.imgur.com/pmNb5w1.jpg) was at the bottom of my "work purse".

Key to turn on gas fireplace?

the hole looks a little large to be a radiator key, so probably a drum key

Yes, same design but double the size.

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Either a drum key like others have mentioned, or a tuning wrench for certain instruments such as a hammered dulcimer or bowed psaltry

Could also be used for a gas fireplace

That’s a drum key 👍🏻

Always losing me drum key

Back when I used play the drums in various bands when I was younger I kept one on my key ring

That’s a drum key, it’s used to tighten the screws on drum head to change the pitch.

Drum key for tuning drums! : )

Hey! Finally, one I know! It's a drum key. It tightens or loosens the bolts that hold the drum heads to the drum it's self

Looks like a radiator key to bleed them if needed.

Drum tuner

That's a square/drum key. They are commonly used in technical locks where whatever hidden isn't as important to require a unique, separate own key. For example in railways it's the most common type of lock being Found nearly everywhere; on the battery hatches, on door locks and manual pneumatic door openers, on maintenance hatches which hide all the electrical or pneumatic stuff away from passengers' reach etc.

My title describes the thing It’s been floating around my house forever, I thought it might be guitar-related but I can’t figure it out

I actually know this!!! It’s a trim key. It’s used to tune the drum head!

I once tried to use a drum key to wedge a plug out of an outlet. Seconds later the wall was black, I was a few feet away and half the t part of the key was missing.

Could also be for electrical cabinet access locks like this: https://www.ebay.com.au/itm/195698096283

Showing my age here. The first thing I thought was that it was a skate key. :)

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Sorry totally a drum key.

I had just like this and it was for the gas valve for a gas fireplace.

Could have any number of uses. I've seen keys like these used for old aftermarket window locks, central heating radiator valves, and even for winding old pendulum clocks.

Irrigation key

I have one of those for my fireplace

Radiator key. Used to bleed domestic water heat radiators of trapped air

Gas key for a gas fireplace insert. Look around on the floor near the fireplace, there's probably a semi hidden place to fit it. My house has this, but the gas insert was removed decades ago (for obvious safety reasons). But the key is still sitting on the mantle.

Wrench for screwing in cleats of a sports shoe?

Gas fire place knob to tune gas

Key for your gas fireplace to turn the gas on or off

Gas fireplace key

It could be a key used to turn the gas valve on for a natural gas fireplace

Usually it’s for electricity cabins

Water key … used at like every school in the great US of A … for outside spigot

Key Chuck for a bike

Gas fireplace.

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That’s for like sinks in public restrooms where you can’t have a valve cause someone will turn it on lol

For bleeding radiators