7 inch to 3-1/2 inch Dust Collection Reducer
SKU: GD-RED-7IN-312IN
- 4 in$18.99
- 5 in$22.99
- 6 in$25.99
- 7 in$28.99 (this size)
- 8 in$30.99
Ships in 3 to 5 business days.
3D printed in PETG and made to order. Shipping is a flat $7.95 anywhere in the US.
Works as both a reducer and expander, so one part covers two jobs. Just flip it around.
Printed to standard 7 inch (177.8 mm) and 3-1/2 inch (88.9 mm) duct sizes. The large end is 7 inch and the small end is 3-1/2 inch.
- Standard sizesStandard size shown
- Made in the USAPrinted to order
- Flat $7.95 shippingOne rate, anywhere in the US
- PETG, not brittle PLABuilt for the shop
About This Reducer
Keep your airflow strong from one duct size to the next, so suction does not drop where the pipe steps down. This reducer joins 7 inch and 3-1/2 inch duct with a tapered inside, so air moves smooth and you lose less pull.
Both ends are printed to standard duct sizes, so they push together and hold in most setups. Printed in PETG, made to order in the USA. Why we use PETG.
What You Get
- One PETG reducer, 7 inch on the large end and 3-1/2 inch on the small end
- A tapered inside, so air keeps moving and you lose less pull
- Both ends printed to standard duct sizes, so it pushes on and holds in most setups
- Works as a reducer or an expander, so one part does two jobs
How it fits
- 1
Push the large end onto your 7 inch duct or hose.
- 2
Slide your 3-1/2 inch duct onto the small end.
- 3
Twist a little so both ends seat.
- 4
Run your dust collector and the airflow steps down clean.
Size help
Measure your hose or duct first, in inches or millimeters. Our measuring guide shows how.
Common questions
Which way does the air flow?
Either way. It works as a reducer when air moves from the large end to the small end, and as an expander when you flip it. One part covers both jobs.
Do I need clamps or tape?
Usually not. Both ends are printed to standard duct sizes, so they push on and grip in most setups. Add a wrap of tape at any joint that sees heavy use or if your duct is worn.
Will it fit my duct?
It is sized for 7 inch on the large end and 3-1/2 inch on the small end. If your run uses two sizes we do not stock, send us a note on the contact page.
What is it made of?
PETG, the same plastic on every part we make. Our About page says why.
Need a size we do not stock?
Pick any two duct sizes from 1.25 inch to 4 inch and we print it to order. Every size makes its own priced page.
Build a custom sizeBuild the adapter for your two sizes
Measure your tool and your vac, so more dust goes in the vac and less in the air you breathe.
Build My Adapter