Cable Length (m): 1.2m, Connecting interface: 3.5mm, Frequency response: 7Hz – 40KHz, Impedance: 15ohms, Sensitivity: 105dB.
Just check coupons out (with price alert and history). Let’s see what best price is ATM.
Aliexpress
There’re some similar (or not) items on Aliexpress
You can use link bot to get even lower price:
Click here to search by yourself. Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
1. ($42.68): AFfbG10
2. ($42.68): affbg10
3. ($44.10): aff7off
apply it in your cart after clicking “Proceed to checkout”. Click to copy code and open shop.
Additional Banggood coupons: first page and second page
Old coupons (from the oldest to the newest): 502C6B, 15earbud, TTxBG10, 2019SPEDM, BG3CSUM, bgssaff9, BGBFAFF2019, BGCITYADS2019, EARSP11, BGMPB2020, BGAFF10OFF, bGhOnEy10, 7d18f7, BGSS10%SW, bgshOOp10, BGELIG0920, BG4BW25, BGLOAC1, 13f142, BGa0b145, BGBuscape01
(these codes were not working in latest coupon update, but you can check them out anyway)
Other warehouses/versions
This item is available in 2 another warehouse/versions!
1. China – KZ ZS6 Earphones ($-3)
2. China – KZ ZS6 Earphones Red ($-3)
Price history and price alert
Price history (for all/most countries) for KZ ZS6 Earphones Gray is here. The lowest price was: $27.49.
Price records source(s): Gearbest, 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)).