Just check coupons out (with price alert and history). What is the best price?
Mode: 30s/60s/90s, USB cable length: about 1m, Wave length: 365 + 405nm, Rated input: AC 100 – 240V 50/60Hz 1.5A, Power: 36W
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Latest coupon code price check (UTC time):
Price history and price alert
There is only one database record (it was for $6.99), so you can’t see price history chart.
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)).