ATM you can buy AirAux AS-22 Mini Bluetooth Audio Amplifier 45W for $49.99 (in Banggood). Price history, coupons and price alert are available on this page. Let’s see what best price is ATM.
AirAux AS-22 Mini bluetooth Stereo Digital Amplifier 45W MAX RMS 300W Hi-Fi Class D 2 Channel Integrated Amp Power Amplifier – EU Plug
Latest price update (UTC time):
Banggood ($49.99)
Banggood warehouse is located in China. There are no coupons available at this moment in Banggood. What about the price? Maybe there’re no more promotions for this item, because current price is higher than average (which is equal $43.57)
Link: Banggood product page
Price: $49.99
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BGad84e7, BG6ddd9d, BG524060, BG589b2e, BG8FORMULAMX
(these coupons are old, so probably won’t work)
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
Here is price history (for all/most countries) for AirAux AS-22 Mini Bluetooth Audio Amplifier 45W.
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)).