Key features: crystal processor 4k, metal stream design, one ui tizen, samsung knox security. Specifications: Display: screen size: 55", refresh rate: 50hz, resolution: 4k (3,840 x 2,160), product type: led. Video: picture engine: crystal processor 4k, hdr (high dynamic range): hdr, hdr 10+: support, contrast: mega contrast, contrast enhancer: yes, motion technology: motion xcelerator, ai upscale: 4k upscaling, color booster: yes, filmmaker mode (fmm): yes. Audio: object tracking sound: ots lite, q-symphony: yes, sound output (rms): 20w, speaker type: 2ch, adaptive sound: yes. Smart service: operating system: tizentm smart tv, bixby: yes, built-in voice assistant: alexa, works with ai speaker: alexa google assistant.