I have checked all old coupons and price is 19.99 USD for Roller Abdominal Tonifying Wheel (in Banggood). Basically copy coupon, view price history or create e-mail price alert. Do you want to know what the best price is?
Latest coupon code price check (UTC time):
Banggood (19.99 USD)
Banggood warehouse is located in China. Price? This price is higher than average price (18.29 USD) for this item. Only one coupon available!
Link: Banggood product page
Price without coupon: 21.99 USD
Coupon (19.99 USD): BGTYBR3
(CouponsFromChina.com tip: apply it in your cart after clicking “Proceed to checkout”. Click to copy code and open shop)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): BGTYDX22
(I don’t think these’re gonna work, but you can try ’em out anyway)
Aliexpress
Click here… to search for AB Roller Abdominal Tonifying Wheel Muscle Trainer on Aliexpress
Here are coupons that you can use.
Price history and price alert
Here is price history (for all/most countries) for AB Roller Abdominal Tonifying Wheel Muscle Trainer.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).