The Belkin Ultra HD High Speed HDMI Cable sold in the Apple Store and directly from Belkin advertises that it supports 4K Ultra HD, Dolby Vision HDR, and 48 Gb/s for its 2 m/6.6 ft cable on its packaging. This is the first HDMI 48 Gbs/s cable released in the market and can use HDMI 2.1 to connect to your Apple 4K or HD TV's or displays, as well as Mac's, PC's or other devices that support HDMI.
Using the GRL DI20 cable tester to test the insertion loss (IL) through the Belkin Ultra HD High Speed HDMI Cable, we can see the cable has lower overall signal integrity performance when compared to the Cable Matters Ultra 8K HDMI Cable (2m) even though they are the same length. The Belkin Ultra HD High Speed HDMI Cable also has higher loss under 10 GHz compared to the Cable Matters Ultra 8K HDMI Cable (2m).
Here's a closer look at the Belkin Ultra HD High Speed HDMI Cable purchased from a Challenger retail store in Singapore.
The Belkin Ultra HD High Speed HDMI Cable states that it supports HDMI output of up to 4K@120Hz or 8K@60Hz.