I have two very short adjustable jack stands that came with my trailer from the previous owner.
Very lightweight, the bases are actually plastic! But they do the job well.
The vertical post is metal and is threaded into the base.
The trailer is so light
you can lift up on the rear bumper to slide the stands underneath.
A long time ago I was towing a pop-up camper down the highway when one of the welded support stands broke off and hit the windshield of the car behind me.
Luckily it only cracked their windshield. It could have been much worse. We exchanged insurance info but I never heard from them.
I'll stick to the portable stands now.