I saw a lot of portable monitor on Amazon but most of them are from sone unknown Chinese manufacture and reading reviews after few weeks some component may break or LCD star displaying bad pixel
Read reviews and choose one with great reviews and MANY of them.
On the reviews page, punch words like Mac and macOS into the search box to search for any reference to using them with Macs too.
Also do searches for any other reviews for any favorites. Google is your friend here. Others will have already purchased a favorite and probably posted some kind of review online or maybe a video review on YouTube.
I just tried a search for "Best Portable Monitors 4K" and it led to one by PCmag with a bunch of name brand portable monitors. I'm sure that's not the only such list either.
Note too that any smallish TV and/or projector might offer OTHER ways to get to mostly the same destination via an HDMI connection.
I have 2x the UPERFECT 4K 15.6"portable monitor that I purchased in 2020 and 1x cocopar 17.3", and I've not had any problems with them. They are all still working perfectly.
Ive spent several months looking for a portable monitor. Was looking for 16" and 500 nits to match the MacBook Air. I looked and considered them all, UPerfect, Rampoo, Innosense, MNM, UYY, Cocoapair, Dose play, VisionOwl.
I highly recommend this one as I'm still blown away by how good this monitor is. I was on the fence with a no name brand but Ive been very impressed and completely surprised by how good this Arozpoa monitor is. I got it for $160CAD, a steal of a deal. It only weighs 1.4lbs. I got a sleeve bag for it and its great.
It works perfect with Mac book Air and I put the screen side by side with the Air and honestly it's just as good for colors and brightness as the MacBook screen is. Very high quality display.
I got it for the 16:10 aspect ratio, 2500k resolution (super sharp) and 500 nits. The build in kickstand is very high quality and just love the whole unit. Very high quality display and great metal build, the entire unit including the kickstand is metal. Ive considered all the monitors and it will be hard to beat this quality monitor for this price. I'm even considering buying a 2nd one but I'm trying to find a use case for it haha. It's just such a good buy and full of buck for your bang.
UPERFECT monitor for PC and laptops which supports Thunderbolt 3 and mobile phones which supports USB 3.1. The Vesa mount is easy to install and suitable for mobile office and desktop use.
www.uperfectmonitor.com
It was about 100€ a branded one like Lenovo, Dell, Acer would cost more than double and some of them also use a pretty old technology