$4.59 – XT90 Male to XT60 Female RC Plug (Banggood, Aliexpress: Body Material: Copper (gold plated), Plug: XT90 Male to XT60 Female Plug, Insulator Material: Nylon (the best price with coupon)).
You can get XT90 Male to XT60 Female RC Plug for $4.59 using coupon code (in Banggood). Check coupons or create price alert down below. You probably want to know what is the best price?
Latest price update (UTC time):
Banggood ($4.59)
Banggood warehouse is located in China. I don’t think there is an active coupon right now – at least in my database. What about the price? From what I can see this price is higher than average price ($4.08).
Link: Banggood product page
Price: $4.59
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/feV
Old coupons (from the oldest to the newest): BGToys8, BGMatt2022, BG589b2e
(these coupons are old, so probably won’t work)
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.
Price history and price alert
Here is price history (for all/most countries) for XT90 Male to XT60 Female RC Plug. The lowest price was: $3.53.
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)).