Helix - Swing Arm Protractor - 180 Degree Rotation

I got this for my daughter's math as she's learning about all things angles. She likes the swing arm and how it helps draw them better.

I sell my notes because I take thorough ones. And while a protractor isn't strictly necessary for diagrams in calculus, as someone who can't even draw a straight line or a circle that doesn't look like a deflated balloon, having a straight edge and circular edge makes my notes look more professional and attractive.You can also detach the angled arm when you need the inner semi-circle edge.The plastic is of high quality, doesn't shatter or scratch easily, and the best part? I take my notes on a digital notebook (ReMarkable II) and the pen and surface don't bug out when the protractor is used (though that might be more praise for the ReMarkable than the protractor - but the point is that the protractor is digital-surface friendly.)It's great. If you need a nice tight little trig/calculus protractor, this guy will deliver.

I purchased this slide arm protractor for use in critical map navigation. The base of the rotating arm includes a hole which enables one to insert the tip of a metal divider or pencil, or a tack, to anchor the protractor in place or draw a perfect dot at zero. Only high quality swing arm protractors have this useful feature in my experience. The rotating mechanism and arm are of robust construction and should last many years. Measurement indicia appear accurate and will not easily rub off. My sole regret is I could have acquired for less money.

Came cracked but not severed, useable but it is what it is, not as accurate as I hoped but for a couple of bucks what do you expect

This protractor is accurate and a lot higher quality than I've used in the past. The plastic is substantial and designed to hold up. I'm rough on this kind of thing, but I believe it will hold up. Recommended.

I've ordered a few protractors for school and this is probably the best I've ever had! I don't use them for crazy architecture, high level math or anything; just basic stuff (this semester it was for geography); so I may not have the proper knowledge to compare this to anything professional. But for general usage this is pretty sturdy and isn't annoying like those other dollar protractors. Everything is aligned, the angle ruler thing wasn't in an awkward place, ALL numbers and lines were dark and very easy to see. Not to mention I've dropped it a few times and it hasn't cracked. Basically, it is perfect! Can't beat the price too!!!

This protector makes measuring angles for my 4th grader pretty easy.

Mechanically, this is a pretty nice swing-arm protractor, but the colors do cause issues. As other reviewers have noted, the dark blue color background color makes it difficult to use. This isn't a translucent blue either, it's a completely opaque coating on the backside. This definitely limits how you use it, if the circle you are measuring is inside it then you'll have to get creative....why didn't they just make it clear?Also, as a reply to other reviewers, you have to be careful with it to get accurate measurements. It's a feature, not a bug that one side is higher than the other, so the swing arm can rest on the right hand side and act as part of the guide. The only downside with this design is that in order to stay within tolerances, this swing arm can swing past 180 degrees and must placed manually at the correct angle.