I have just checked coupons. The lowest price I could get is 8.54 USD for Adhesive Metric (in Banggood). Just check coupons out (with price alert and history). Let’s see what best price is ATM.
Latest coupon and price update (UTC):
Banggood (8.54 USD)
Banggood warehouse is located in China. As you can see I didn’t find any active coupon for this product right now… You probably want to know if this is a good price. Maybe there’re no more promotions for this item, because current price is higher than average (which is equal 5.41 USD)
Link: Banggood product page
Price: 8.54 USD
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): BG2578675, BGDRB18, BGWT15, BGWDT15, BG20236Tool
(sometimes old coupons work, so you can check them out (this site checks them on every price update))
Aliexpress
Click here… to search for Self Adhesive Metric Ruler Miter Track 1m on Aliexpress
Here are coupons that you can use.
Price history and price alert
Price history (for all/most countries) for Self Adhesive Metric Ruler Miter Track 1m is here.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).