# What are these bolt receptacles called? **URL:** \ **Category:** Factual Questions\ **Created:** [December 2, 2021, 4:02am UTC](https://boards.straightdope.com/t/what-are-these-bolt-receptacles-called/955335 "2021-12-02T04:02:34Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Nars\_Glinley](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/nars_glinley/32/8177_2.png) [@Nars\_Glinley](https://boards.straightdope.com/u/Nars_Glinley)\ **Post date:** [December 2, 2021, 4:02am UTC](https://boards.straightdope.com/t/what-are-these-bolt-receptacles-called/955335/1 "2021-12-02T04:02:34Z")
I’m trying to fix my beloved office chair and am at my wit’s end. All I really want to do is to change the cylinder but this one is stuck TIGHT. I’ll keep working on that, but in the meantime, I’m considering replacing the control plate and mechanism. Unfortunately, the hole pattern seems to be unlike any other chair ever. I’m thinking about getting a standard size, drilling new holes and attaching it. What are the things that the bolts screw into called? It looks like they drilled a hole into the plywood base of the chair and then hammered these threaded “things” into them. I might need to order some if I can’t get the cylinder off but I don’t know what they’re called. TIA. ---
**Author:** ![Snowboarder\_Bo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/snowboarder_bo/32/229_2.png) [@Snowboarder\_Bo](https://boards.straightdope.com/u/Snowboarder_Bo)\ **Post date:** [December 2, 2021, 4:07am UTC](https://boards.straightdope.com/t/what-are-these-bolt-receptacles-called/955335/2 "2021-12-02T04:07:23Z")
T-nuts. > **[3/8"-16 T-Nuts (200 Pack), Zinc-Plated Steel Corrosion Resistant, 7/16" Barrel...](https://www.amazon.com/Bolt-Dropper-Pronged-Climbing-Cabinetry/dp/B06X1FMTWY)** > > 3/8"-16 T-Nuts (200 Pack), Zinc-Plated Steel Corrosion Resistant, 7/16" Barrel Length, 4-Pronged Tee Nut for Wood, Rock Climbing Holds, Cabinetry by Bolt Dropper: Amazon.com: Industrial & Scientific ---
**Author:** ![Nars\_Glinley](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/nars_glinley/32/8177_2.png) [@Nars\_Glinley](https://boards.straightdope.com/u/Nars_Glinley)\ **Post date:** [December 2, 2021, 4:09am UTC](https://boards.straightdope.com/t/what-are-these-bolt-receptacles-called/955335/3 "2021-12-02T04:09:41Z")
Perfect. Thank you! ---
**Author:** ![Snowboarder\_Bo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/snowboarder_bo/32/229_2.png) [@Snowboarder\_Bo](https://boards.straightdope.com/u/Snowboarder_Bo)\ **Post date:** [December 2, 2021, 4:10am UTC](https://boards.straightdope.com/t/what-are-these-bolt-receptacles-called/955335/4 "2021-12-02T04:10:36Z")
You’re welcome. Super-useful piece of hardware. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [December 2, 2021, 9:53am UTC](https://boards.straightdope.com/t/what-are-these-bolt-receptacles-called/955335/5 "2021-12-02T09:53:46Z")
There are also these (same general idea, but they screw into place rather than hammer in): > **[Amazon.com: 40Pcs Anwenk 1/4"-20 x 15mm Furniture Screw in Nut Threaded Wood...](https://www.amazon.com/Anwenk-Furniture-Threaded-Connector-Assortment/dp/B07HR63VF5)** > > Buy 40Pcs Anwenk 1/4"-20 x 15mm Furniture Screw in Nut Threaded Wood Inserts Bolt Fastener Connector Hex Socket Drive for Wood Furniture Assortment (with Hex Spanner): Nut Inserts - Amazon.com ✓ FREE DELIVERY possible on eligible purchases ---
**Author:** ![bob\_2](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bob_2/32/3341_2.png) [@bob\_2](https://boards.straightdope.com/u/bob_2)\ **Post date:** [December 2, 2021, 10:35am UTC](https://boards.straightdope.com/t/what-are-these-bolt-receptacles-called/955335/6 "2021-12-02T10:35:42Z")
If the fastener is subject to being pulled, the first type would not be suitable. It would be excellent as a captive bolt on the back of a plywood sheet though. In end grain, or wherever the bolt does not go through the material, I think the screw-in type, with maybe some glue for extra strength, would be better. ---
**Author:** ![Retzbu\_Tox](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/retzbu_tox/32/11829_2.png) [@Retzbu\_Tox](https://boards.straightdope.com/u/Retzbu_Tox)\ **Post date:** [December 5, 2021, 6:38pm UTC](https://boards.straightdope.com/t/what-are-these-bolt-receptacles-called/955335/7 "2021-12-05T18:38:24Z")
Prior to reading this post several days ago, I had never before heard of pronged T-nuts. Two days ago, I was helping my mother put up some Christmas decorations, and she lamented the broken stakes on some of her yard ornaments. I proclaimed, “Oh, those are put together with pronged T-nuts! I just read about those.” I made new stakes and attached them to her decorations. Today, news articles from MSN keep showing me advertisements for T-nuts from Amazon. Curse you, interwebs!