Skip to main content
GulpDust

1-1/4 in. (31.75mm) Dust Port Tools and Vacuum Adapter Guide for DeWalt, Milwaukee, and Porter-Cable

1-1/4 in. inner35mm outer1-1/4 in.5 tools

A 1-1/4 in. (31.75mm) port is the most common cordless hand-tool standard in the US. The port is round, about 31.75mm across on the inside and about 35mm on the outside. Many DeWalt 20V MAX and FlexVolt 60V tools use it, so do a handful of Milwaukee M18 saws and a Porter-Cable sander.

If you do not own a DeWalt or Milwaukee branded vac, your shop vac hose is the wrong size. A 1-7/8 in. or 2-1/2 in. hose end is much larger than 31.75mm. A sized PETG adapter bridges the gap so the tool pulls dust into the vac instead of past it.

Below is every tool with a 31.75mm dust port that we track. Each link goes to that tool's full page with the exact size and the adapter that fits.

Power Tools With a 1-1/4 in. Dust Port

Every tool we list with a 1-1/4 in. port. Linked tools open their full specs and the exact adapter that fits.

The Adapter That Fits a 1-1/4 in. Port

Each adapter grips the 1-1/4 in. inside of the tool port on one end and steps it to your shop vac or dust extractor hose on the other end. Friction fit, no clamps. Made in the USA.

What 1-1/4 in. (31.75mm) Means on a Tool Port

A 1-1/4 in. port measures about 31.75mm across on the inside. On the outside it usually runs about 35mm. The port is round and uses a friction fit, so a sized adapter pushes on and stays put.

The DCW600B router runs a touch under at 31.2mm inside. The Milwaukee 2732-20 circular saw and the DCS520T1 track saw are the full 31.75mm inside. The 0.55mm gap between 31.2 and 31.75 falls inside the PETG friction-fit clearance, so one adapter snugs into both.

Most US shop vac hoses are 1-7/8 in. or 2-1/2 in., both much wider than 1-1/4 in. That gap is why a hose laid against the tool port leaks dust into the air instead of into the vac.

How to Find Your Tool's Port Size

Open the tool detail page on this site for your specific model. The page shows the port size in millimeters and the adapter that fits it.

If your model is not in the list above, measure the port with calipers. Close the jaws around the OUTSIDE of the port stub. That is your outer diameter. The inside diameter is your stub-fit target. Round to the nearest standard size if your number falls between two.

Why One Adapter Size Covers These Different Tools

Every tool listed above has a round 31.75mm interior port (the DCW600B is a touch under at 31.2mm). The adapter sized for 31.75mm has the friction clearance to seat in all five.

Outside of the five above, do not assume the 1-1/4 in. label on a different cordless tool means it is exactly 31.75mm. The Milwaukee 2723-20 router ships 'M18' branded, but its port is tapered, about 30mm at the grip and 34.6mm at the lip. That is a different shape, and a straight cylinder will not seat. Use the tool detail page for the tool you own.

1-1/4 in. Dust Port FAQ

Which power tools use the 1-1/4 in. (31.75mm) port?

Five tools have a 1-1/4 in. dust port that we ship an adapter for: the DeWalt DCW600B router (31.2mm inside), the Milwaukee 2732-20 M18 FUEL 7-1/4 in. circular saw, the DeWalt DCS520T1 FlexVolt 60V track saw, the DeWalt DCS520B 20V MAX XR track saw, and the Porter-Cable PCC761B random orbit sander. Many other cordless tools show about this size on the package. Open the detail page for the tool you own.

Why is the DCW600B listed at 31.2mm if the hub is 31.75mm?

The DCW600B port is 31.2mm inside and 38.6mm outside. The 0.55mm gap to a 31.75mm adapter sits inside the PETG friction-fit clearance, so the same adapter seats on both. We list the DCW600B here because it shares the same adapter, not because the port measures exactly 31.75mm.

Does the Milwaukee 2723-20 router belong on this hub?

No. The 2723-20 has a tapered port, about 30mm at the grip and about 34.6mm at the lip. A straight 31.75mm adapter will not seat right. Use the 2723-20 tool detail page for the tapered adapter made for it.

Can I use a regular shop vac with these tools?

Yes, with the right adapter. A 1-7/8 in. or 2-1/2 in. shop vac hose is much wider than 31.75mm. The GulpDust PETG adapter is sized to the 1-1/4 in. tool port on one end and to your shop vac hose on the other.

Do you sell the design file?

No. We sell the finished part. Each 31.75mm adapter is printed to order in PETG and ships from the US.

Other Dust Port Sizes