List price is $80. Gets good reviews.
Amazon.com: Denali 18-Inch Digital Angle Protractor with Carrying Case: Home Improvement
- Take the guesswork out of measuring, marking and reading angles—no tricky geometry or complicated calculations required—with the Denali Digital Angle Protractor. Simply swing open the tool’s pivoting leg and immediately read the angle on the digital display window. The tool is accurate within 1 degree, and will read angles ranging from zero to 185 degrees. The anodized-aluminum protractor is also fitted with two bubble vials for use as a conventional level.
The Denali Digital Angle Protractor weighs just over a pound, and measures a slim 1 inch by 2 inches by 18 inches. It’s powered a single 9-volt battery (included) that typically lasts about 100 hours of normal use. The tool comes with a protective carrying case that’s equipped with a convenient steel belt clip.
The protractor provides a quick and precise way to read existing angles, such as roof slopes, wall corners, handrails, and mitered trim work. You can also use it to mark any desired angle up to 185 degrees. It’s an indispensable tool when installing crown molding; use it to determine the angle of outside corners, which are rarely 90 degrees. This versatile tool will also do many of the jobs typically reserved for a sliding T-bevel square. And if all that weren’t enough, the Denali Digital Angle Protractor costs about three times less than any comparable tool on the market
Denali 18-Inch Digital Angle Protractor with Carrying Case $34.99 at amazon 
