Amazon.com: avedio links HDMI Splitter 1 in 2 Out, 4K HDMI Splitter for Dual Monitors Duplicate/Mirror Only, 1x2 HDMI Splitter 1 to 2 Amplifier for Full HD 1080P 3D with HDMI Cable (
Amazon.com: HDMI Splitter 1 in 2 Out 4K, Anbear HDMI (Duplicate/Mirror) Dual Monitors 1x2 HDMI for Full HD 1080P 3D with High Speed HDMI Cable : Electronics
HDMI 2.1 vs. DisplayPort 2.0
Can I plug an HDMI 2.1 into a 1.4 slot? - Quora
The HDMI 2.1 low-down: Don't dump your legacy cables | TechHive
HDMI Splitter 1 in 2 Out - YouTube
HDMI 2.1a Specification Overview
HDMI Switch 2 In 1 Out 1080P 4K HDMI Switcher Box Auto Splitter - Walmart.com