What kind of Fastener is this?

As usual I've been taking apart things and I've noticed an unusual fastener, it looks like a rivet but its melted plastic. I was just wondering how it works (i.e. how they melt it, special equipment or diy?). My xbox had one on it and I've noticed a couple of other electronics that have them as well. Googling plastic rivet didn't give me anything close. I do a lot of repairs so adding a new fastener to my list would give me more options for making a repair / mod look more professional. I took a pic of it below.

Picture of What kind of Fastener is this?
Lorek (author) 6 years ago
Thanks, googling ultrasonic welders came up with a wealth of information about the process. I'll have to see about building a DIY version, maybe an instructable we'll see if its doable.
As L. Says, but quite often they are set by ultrasonic welders.
lemonie6 years ago
Yes it's melted-plastic "riveting". The round bits were plastic sticks until they were squashed with hot-metal.