Ultrasonic Solar Cat Dog Pest Repeller (Banggood, Aliexpress: Brand KCASA, Detection Range 8 – 9 meters depending on animals size, Infrared Sensor Angle 110 degrees, Power Supply Solar power + 3x AA size rechargeable batteries or 5V / 500mA adaptor, Red Light Indicates the units is activated, Model KC-JK550 (the best price with coupon)).
Price history, coupons and price alert are available on this page. 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 price update (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
1. ($33.29): BG081591
2. ($34.77): BG589b2e
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/feV
Old coupons (from the oldest to the newest): BGfa5d3a, BG3397e7, BG5cd82e, BGed41a8, BG3aeccb, Cuponation9, BG8ReviTrage, BGcoupon8off, BGGutscheine, BG00c906, BG8OFFCOUPON, TTBLACK5, BGdbe184, BGf625a4, BG23ALEAprD
(there’s a little possibility that old coupon will work)
Price history and price alert
Check out price history chart (for all/most countries) for Ultrasonic Solar Cat Dog Pest Repeller. The lowest price was: $19.99.
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)).