In stock
Grouped product items
Product Name Price Qty
4" to 2-1/4" Hose Reducer (OD)
4" to 2-1/4" Hose Reducer (OD) Item #: 23486
In stock
4" to 2" Hose Reducer (OD)
4" to 2" Hose Reducer (OD) Item #: 20387
In stock

Hose Reducers

Item #
92% of 100
Hose Reducers Hose Reducers Hose Reducers Hose Reducers
Hose Reducers

Attach two hoses of different diameters together. Step down in size increases air velocity near the machine where its needed most.

(1) Hose Reducer
More Information
Brand No
Manufacturer Part Number No
Weight 0.2400
Tech Spec Item #: 23486
  • Small Opening OD: 2-1/4''
  • Large Opening OD: 4''

Item #: 20387
  • Small Opening OD: 2''
  • Large Opening OD: 4''

Technical Documents No
Size 2-1/2", 4"
Material Plastic
Type Reducer
Prop 65 WarningWARNING: Cancer & Reproductive Harm -

Prop 65 WarningWARNING: Drilling, sawing, sanding or machining wood products can expose you to wood dust, a substance known to the State of California to cause cancer. Avoid inhaling wood dust or use a dust mask or other safeguards for personal protection. For more information go to
4.6 / 5.0
22 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
Good Product
Reducer works great, Solid and strong, will last for as long as I will need it. I recommend this reducer for sure. size is perfect fit
August 14, 2018
2 months ago
Woodworking Experience:
Works as it’s supposed to
Very secure and air tight.
August 10, 2018
2 months ago
Woodworking Experience:
Perfect for my job
April 3, 2018
7 months ago
Woodworking Experience:
It works great don’t have to change hose end anymore there great
February 15, 2018
8 months ago
works great
works great
December 30, 2017
9 months ago
Great product
Perfect fit. Just as described!!!
December 29, 2017
10 months ago
Woodworking Experience:
Nice reducer, needs connector
My grizzly 2HP bandsaw has a 4" opening. My grizzly 5HP jointer/planer has the same. This item requires a 4" cuff to join the pieces, or duct tape or gaffer's tape to make it stay. Otherwise, it butts right up against the opening and does not stay. Also, the small end does not fit my wet/dry vacuum hose perfectly. It is slightly smaller. The inner and outer diameters of my shop hose are 2" ID and 2.25" OD. I put a few rings of gaffers tape around the small opening and it fits snugly now. It works great, but I needed to do a little rigging.
June 20, 2017
1 year ago
Woodworking Experience:
Very good..
Very good..
March 27, 2017
1 year ago
Worked prefect for my application.
March 17, 2017
1 year ago
Hose reducer
Fits perfectly onto my Dust Deputy that has a 2.5" or 2.25 " port. that port actually widens towards the back making a nice snug fit for the hose reducer.

The other end fits to the hose but Rocklers hose tends to be tight to the point that it needs to be stretched out a bit. And it is stretchable.
December 30, 2016
1 year ago
Woodworking Experience:
Start typing your question and we'll check if it was already asked and answered. Learn More
Browse 8 questions Browse 8 questions and 54 answers
Why did you choose this?
Rockler Store
to match my shop vac
Stephen M on Jul 22, 2018
Rockler is convenient; item is exactly what I need
John K on May 2, 2018
to match my shop vac
Stephen M on Jul 22, 2018
I chose this item to fit my machine ports
Crackerjackman on Jul 4, 2018
Rockler is convenient; item is exactly what I need
John K on May 2, 2018
for use with shop-vac
Tom M on Mar 27, 2018
to use on my planer
Richard S on Mar 17, 2018
for my drum sander
john y on Mar 10, 2018
I needed it.
David T on Feb 10, 2018
To attach to my ShopVac
J M on Feb 3, 2018
attach to smaller equipment ports
Charmaine R on Dec 31, 2017
Part of 4" dust collection system
N H W on Dec 30, 2017
you are the place to purchase wood working supplies
Paul w M on Dec 22, 2017
The Dust Right 4" Tool Port and the 4" to 2-1/4" Hose Reducer are needed to connect the Rockler Dust Right handle to the Dust Right Universal Small Port Hose Kit.
Robert L H on Dec 4, 2017
Dust collection system.
Robert L on Nov 16, 2017
Got me some tools to connect
Herbert S on Nov 2, 2017
It fits the adapter on the hose
Robert J on Oct 23, 2017
Need it for my dust collection system
Dewayne H on Oct 13, 2017
John M on Sep 12, 2017
my husband told me to!
Janet M on Jul 27, 2017
to go from a 4"installed system to a smaller more manageable hose with longer reach.
Benjamin F on Jul 21, 2017
need it
daniel z on Jul 20, 2017
necessary for my system
jay k on Jul 6, 2017
I have a central vacuum system and need this for smaller connection to tools.
Gary E on Jun 20, 2017
connect planer to super max dust collector
Patrick M on Jun 9, 2017
They fit the machines that I have.
jay k on May 25, 2017
To fit 4" hose to 2 1/4" fitting!
Margretta E H on Mar 21, 2017
frank c on Mar 6, 2017
Donald W on Mar 5, 2017
Excellent product. Fits right on
Guillermo O on Mar 4, 2017
I needed it.
DARRYL P on Feb 26, 2017
to connect 4in port off of ridgid jointer to shop vac
Stu B on Feb 20, 2017
To attach my dust collector hose directly to machines while using them for more direct & complete capture of chips and dust.
Veryl K on Feb 15, 2017
Need to reduce from dust hood outlet to shop vac hose.
Steve J on Feb 4, 2017
need it
Michael C on Jan 28, 2017
Connects my band saw to 4" hose.
DadGran on Jan 20, 2017
to hook up my dust collection system to various tools
Karen M. C on Jan 17, 2017
Need them for my vac system in my home workshop.
robert g on Dec 30, 2016
To complete our new table saw
Karen S on Dec 29, 2016
I needed this for the vacuum hose to reduce to fit my other tools.
STEVE L on Dec 17, 2016
upgrading dust collection from shop vac system to 4" dust collection system.
Michael H on Dec 14, 2016
To adapt to my machine
Gerald D on Dec 12, 2016
Efficient connection of the 4" flex hose to equipment.
Roger L. S on Dec 7, 2016
Part for new dust collection system
Joe S on Dec 6, 2016
to adapt a shop vac to my table saw
william c on Dec 4, 2016
To adapt a smaller hose to my 4" DC pipe
Gerald V on Nov 30, 2016
Again, it allows flexibility with my shop equipment.
Robert C on Nov 30, 2016
I have several tools that use the 4" size. I needed this to modify my vac hose to work with these tools.
Rob on Nov 27, 2016
For the new saw I purchased
David B on Nov 27, 2016
Needed to hook dust collection to Dewalt DW735 planer.
Timothy E. K on Nov 15, 2016
I need it
Kevin K on Nov 1, 2016
I need to reduce the dust port on my table saw to fit the hose on my shop vac.
Richard S on Oct 29, 2016
I chose this item to fit my machine ports
Crackerjackman on Jul 4, 2018
for use with shop-vac
Tom M on Mar 27, 2018
20387. Are the stated dimensions ID or OD?
A shopper on Jul 10, 2015
I want a fitting that attaches to my joiner to a shop vac? The hole diameter of my joiner is 3.62 & my shop vac hose is 2.5".
James G on Jan 2, 2016
Will the 4" to 2-1/4" Hose Reducer work on a Dewalt DW735X planer?
Rob B on Nov 3, 2016
BEST ANSWER: I just found out that it does NOT fit, as the 4" diameter is equal to the size of the outflow from the planer :-(
What is the ID on the small side of the 20387 and 23486 fittings?
Craig K on Nov 18, 2015
BEST ANSWER: 20387 would have a 1-3/4" id, 23486 would have a 2" id
I have a 4" port that comes out from my Band saw, I need the reducer to fit over that port so that it connects properly. will that fit over the 4" port?
Paul L on Feb 3, 2016
BEST ANSWER: Fits over the 4" port of my Dewalt 734 planer nice and snug. No reason to think it wouldn't work in your 4" bandsaw port.
Will this fitting connect a 2-1/2" dust right hose to a dust deputy port?
Allen W on Jul 8, 2018
Just received the 4" dust seperator components and have installed in a 30 gallon can. States the 4" hose with clamps work with the system. I have a 5hp vacuum with a 2 1/4 " hose, your fittings all appear to be the same exact size and will not fit. What size will fit to make this operational?
Michael P on Jul 6, 2018
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