You can get ENJOYWOOD 3D Multi-Angle Measuring Ruler Square for $9.99 with coupon (from Banggood). Go down and check coupons out. Remember to check price history if it is available. What is best price?
Latest price update (UTC time):
ENJOYWOOD 3D Multi-Angle Measuring Ruler Square Protractor Hole Positioning Inch/MM Imperial Metric Durable Aluminum Alloy T-Type Triangle Scriber Tool Ideal for Woodworking Measuring Angles 22.5/30/45/60/67.5/90 Degrees – Metric
Banggood ($9.99)
Banggood warehouse is located in China. I’m afraid that there’s no working coupon in Banggood. Price? Looks like a good price to me (average is $10.11).
Link: Banggood product page
Price: $9.99
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Price history and price alert
Check out price history chart (for all/most countries) for ENJOYWOOD 3D Multi-Angle Measuring Ruler Square.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).