A:Answer Each series builds on each other. Both of these series are 4K UHD, have HDR support, and have a Roku operating system. The 5-Series additionally has Dolby Vision Support, wide color gamut, auto-game mode, an edge-to-edge glass display, etc. You can also visit www.tclusa.com/products/home-theater/5-series and scroll down to "Compare All Models" to see all models compared. Hope this helps! Thank you, TCL Customer Support
