DEWALT 7/8-in. 1/2-in. Drive 6-Point Deep Impact Socket, SAE (DWMT73940OSP)
DEWALT 7/8-in. 1/2-in. Drive 6-Point Deep Impact Socket, SAE (DWMT73940OSP)
Out of Stock - Available to Order - Usually ships in 14-30 days
Product Details
Product Details
Key Features
Overview
The DeWalt DWMT73940OSP Mechanics 6 Point 1/2 in. Drive Deep Impact Socket 7/8 in. SAE is a single deep impact socket built for mechanics, automotive work, and anyone using a 1/2 inch drive ratchet or impact setup on larger SAE fasteners. This is a deep impact socket designed for fastening and loosening 7/8 inch SAE nuts and bolts. Model Number: DWMT73940OSP.
The main reason to choose this socket is simple: it handles a common larger fastener size in a deep pattern that works better when the fastener sits on a longer stud or below the surface. That extra depth makes it more useful for jobs where a standard shallow socket can bottom out before it fully seats. The 6-point opening is the right choice when you want stronger engagement on the flats of the fastener instead of putting more stress on the corners.
DeWalt builds the DWMT73940OSP from premium chrome vanadium steel, which matters because sockets live a hard life. They get thrown in drawers, rolled around carts, and used in dirty environments where durability matters more than looks. Chrome vanadium is a proven material for this kind of hand tool because it balances toughness and long-term wear resistance.
One of the better practical details here is the knurled beauty ring. That gives you a little more grip when you are handling the socket by hand, especially when your fingers are slick with oil, grease, or road grime. It is not a flashy feature, but it is exactly the kind of small shop detail that makes daily use less annoying.
Because this is a 1/2 inch drive deep socket in a 7/8 inch SAE size, it fits naturally into automotive and mechanical tool kits built around standard 1/2 inch drive ratchets, breaker bars, and compatible impact tools. If you already work in that drive size, this socket drops right into the system you are already using without any extra adapters or oddball setup.
This socket makes the most sense for automotive technicians, fleet maintenance crews, farm equipment owners, and serious DIY users who need a dedicated larger SAE deep socket instead of making do with adapters or shallow sockets that do not reach. If you are working on lug-related service, suspension hardware, or other larger fasteners where depth matters, this is the kind of single socket worth keeping in the box.
DeWalt DWMT73940OSP Deep Socket Reach
A deep impact socket earns its keep when a shallow socket will not fully seat over a nut on a long stud. That is the practical advantage here: better access without changing your whole setup.
- 7/8 inch SAE socket size for larger standard fasteners
- 1/2 inch drive fits common ratchets, breaker bars, and impact tool setups
- 6-point design gives solid contact on the flats of the fastener
What's in the Box
- (1) DeWalt DWMT73940OSP 7/8 in. SAE Deep Impact Socket
Key Specifications
| Drive Size | 1/2 in. |
|---|---|
| Socket Size | 7/8 in. |
| Measurement System | SAE |
| Point Type | 6-Point |
| Socket Type | Deep Impact Socket |
| Material | Chrome Vanadium Steel |
| Piece Count | 1 |
Compatibility
Built For
Pro Tip
If you are working on a nut that sits on a long stud, reach for the deep socket first instead of stacking adapters and extensions. You will get a cleaner fit and fewer chances for wobble at the fastener.
Tool Nut's Take
One of those single sockets that saves time fast
The DeWalt DWMT73940OSP is the kind of dedicated deep socket that makes sense the minute you run into a longer stud and realize a shallow socket is not getting it done.
- Who it's for: Techs, mechanics, and serious DIY users who already work with 1/2 inch drive tools and need a 7/8 inch SAE deep socket in the box.
- Why it stands out: You get a practical 6-point deep design, chrome vanadium steel construction, and a knurled ring that makes handling easier when the shop gets greasy.
- Worth knowing: This is a single socket, not a set, so it is best for filling a specific gap in your lineup or replacing a size you use often.
Common Questions
- What size fastener is this socket made for? It is a 7/8 in. SAE socket.
- What drive size does it use? It uses a 1/2 in. drive.
- Is it a 6-point or 12-point socket? It is a 6-point socket.
- Is this a shallow or deep socket? It is a deep impact socket.

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