Battery 3x 1.5V(AAA) (Not included), Product size 163mmx 55mmx 28mm, Product weight 118g, Working environment 0~40° C (≤80%RH), 40~50° C (≤45%RH), Full battery duration >12hrs with bluetooth function on, Storage environment -20~60° C (≤75%RH).
Just check coupons out (with price alert and history). You probably want to know what is the best price?
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. There is one coupon right now! Check this out.
Link: Banggood product page
1. ($32.21): BGGines
this code has to be applied 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): 0e7f33, FBCOUPON1, BGherra, Tabby20
(probably won’t work, but you can try them out)
Price history and price alert
Price history (for all/most countries) for UNI-T UT383BT Bluetooth Luxmeter is here. The lowest price was: $20.6.
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)).