I saw this on one of my auction sites and it rang alarm bells in my mind. They call this a 3000w instant water heater but they sell it with a NEMA 5-15 plug. I did some research on these on other sites and they appear to actually be a 240v heater (12.5a) that they put a 120v plug on. That makes it a 750w heater.
OTOH if the actually did make a 3kw heater at 120v it would be 25a. They say 32a but they spec 2.5mm wire (somewhere between #14 and #12).
This whole thing doesn't add up if you read the description but since the reviews don't talk about tripping breakers I am guessing the real answer is it is a 750w heater @ 120v.
Of course it isn't listed
I am not willing to spend the money to find out. 750 watts wouldn't heat much more than a trickle of water (42 BTU/minute)https://www.temu.com/tankless-elect...page_sn=14021&_x_sessn_id=4o3fifk7n0