Air Duct Sizing Calculator

Sturdy good quality should last fir a long time

As advertised. Received quickly and in good condition.

Perfect air duct slide calculator. I removed the stick-on bar code the first day , and it peeled off cleanly.

There was a paper sticker on the back of the slide rule that was on top of a lot of information and it was difficult to get off without ruining it.

I had a duct calculator for about 10 years, but with time it wore out. I was hoping to get one similar to the one I had and took the risk in getting this one. I was glad when I got it, because I was able to read this one as if it were my old one. I am very well pleased with it. Has the same features as my old one did. 👍

I had seen some leave negative feedback because of the sticker on the back. It wasn't hard taking it off. Just peel it with your nail. Comes right off. Great tool. Prefer it over phone apps

tslide rule, one step duct size calculator was fine except for one problem. THE BACK SIDE HAS AN INVENTORY STICKER APPLIED TO THE LOWER BOTTOM, THAT IS UNREMOVABLE MAKING THE FORMULAS UNDER THE STICKER UN-READABLE. THEY NEED TO USE STICKERS THAT ARE EASILY REMOVABLE WITHOUT DAMAGE TO THE CALCULATOR.

This is a great chart to have for properly sizing duct work. With new furnaces, rule of thumb doesn't cut it any more. Back of slide has a chart for calculating friction loss and equivalent length of duct work for most fittings. I use this chart every day for my installs.