Max Charge Capacity: 300W, Power: 400W, Voltage Range: AC 110-220V, 0.1-3A(Internal consumption mode), Supported Batt. Type: LiFe/Lilon/LiPo/LiHv (2-8S), Charge Current: 0.1-15A, Current: 16.6A, Input Voltage: DC 10-30V, Discharge Current: 0.1-15A(Recycling mode), Output Voltage: 0-30V, Max Discharge Capacity: 20W, Size: 222×70×38.8mm, Weight: 668.5g, NiMH/Cd(1-20S), Pb(1-10S).
Just check coupons out (with price alert and history). 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 code price check (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
1. ($53.99): BGAFF10OFF
2. ($53.99): bGhOnEy10
paste coupon code in your cart and click Apply 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): BGToolkitRC10, affbg10, AFfbG10, 502C6B, BGCITYADS2019, BGVDay10%off, BG10BC, BGMPB2020
(you can check these old coupons out, but these probably won’t work)
Price history and price alert
Here is price history (for all/most countries) for ToolkitRC M8 DC 300W 15A RC Battery Charger White With Power Supply. The lowest price was: $49.99.
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)).