Just check coupons out (with price alert and history). You probably want to know what is the best price?
Charging Time (h) 1.5H/2.5-3H, Standby Time (h) 180H+720H, Supported Profiles HSP/HFP/A2DP/AVRCP, Net Weight (g) 160g, Dimensions 10.6cm*9.4cm*4.1cm, Microphone Yes, Music Time 9H+64H, Brand TRN, Charging current DC5V /1A, bluetooth Chip QCC3020, Battery Capacity Earbud: 80mAh, Frequency Response 20 – 20000Hz, Color Black, Charging Box: 700mAh, Wearing Type TWS, Model BT20S PRO, Material ABS+PC, Volume Control Yes, bluetooth Version V5.0, Transmission Distance 33 feet (10m), Support Audio decoding APT / AAC
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
1. ($83.44): BGAlerabatKL
2. ($83.44): BGd173b4
just apply this code in your cart after clicking “Proceed to checkout”. Click to copy code and open shop.
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BGSK635, BG4BW25, BGSK196, BGLOAC1, 13f142, BGa0b145, BGBuscape01, BG651551, BGBRPL2, BGHOTSHOP15, BG53e9c8
(these coupons are old, so probably won’t work)
Price history and price alert
Price history (for all/most countries) for TRN BT20S PRO Bluetooth Headset is here.
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)).