TCL 55-inch 4k Smart TV

Is it this one?:

at $428 and new

Woot!: 55UP120
Wal-Mart: 55US57

Different models, but I’m not really clear on what the differences are between them.

I bought this last time they were offered. This set is fantastic, great picture, easy set up. Remote app for ios works great.

Wasn’t this just offered on here for $50 less?