The 40A4GT is a 40 inch Full HD TV from Hisense. It was launched in 2021. It features a True 8-bit IPS panel.
It can achieve a maximum resolution of 1920 x 1080 with a refresh rate of 60 Hz and pixel density of 55 ppi.
Picture Quality
Now, the very next spec of a display that defines picture quality is its Color Gamut.
This TV doesn't provide a color gamut specification, so we have to make an assumption based on its panel type. This unit comes with an IPS panel. These panels are known to produce great colors out of the box. So we can assume that the sRGB coverage (equivalent) on this TV to be 70% or above. For content consumption and gaming purposes, you may not need any better than this anyway. So its good enough.
What is Color gamut ?
Color gamut spec of a display is the measurement of the range of colors that the display can produce.
A TV with poor color accuracy will produce undersaturated/washed out colors that will spoil the immersion.
It is specified in different units - sRGB(most popular), NTSC 1953, DCI P3 etc. It is upto the manufacturer which one they choose.
But don't worry, below is a chart that you can use to choose a TV with good color accuracy.
Next in the list of important specifications is Static Contrast.
The importance of static contrast ratio
A TV with low static contrast ratio will not produce deep enough blacks and can bleed backlight as shown below:

The above TV's static contrast is 800:1. So make sure you get a TV with a static contrast of >= 1000:1. Ofcourse, More is better.
Note that, static contrast ratio and resolution go hand in hand when it comes to details. To put it into perspective, a TV with low contrast ratio will show both dark gray and black as black, thus lesser detail overall.
However, we couldn't find a static contrast ratio specification for this TV. Once again we have to take a guess. In general, IPS panels come with a static contrast ratio between 700:1 - 1500:1. Now, for a mid-range Full HD TV, we can imagine the ratio of Hisense 40A4GT to be 1200:1 or above.
HLG (Hybrid Log Gamma) and HDR are also supported on this TV, so that's a plus.
As for brightness, the peak luminance the TV can produce is 250 nits with the help of Direct LED backlight.
Gaming Performance
Now if you are planning to use the TV other than watching videos — say as a PC monitor or for gaming purposes, you would want to take a TV with lowest input lag. For gaming however, both input lag and response time impacts the performance.
Sadly, Hisense did not specify the input lag on this unit. Now, IPS panels in general are known for high input lags and response times. So, the input lag on this TV could be above 20ms. Though, Non-FPS and casual games should be playable.
What is Input lag ?
This lag is the latency at which your device inputs changes the content of your TV. Though, this won't matter much if you aren't into competitive/FPS games like call of duty.
Although for better experience, get a TV that comes with an input lag and response time of < 20ms.
Dimensions and Ergonomics
Vertically, the TV measures 40 inches and horizontally 35.16 inches. Speaking of thickness, it is just 3.39 inches thick.
Overall it weighs around 5.5 kgs including its stand. Without stand, it weighs 5.4 Kilograms.
Now, coming to ergonomics — VESA mount is supported on this TV with an interface size of 100 x 200 mm. Swivel, Tilt or Pivot features are not supported on this unit.
Hardware and Audio
To power its UI, the TV runs VIDAA U5.0 Operating System.
For display connectivity, there are two HDMI 2.0 (CEC) ports and one AV Composite In (Video + L/R) port on this TV.
To connect USB devices, you have — 1x USB 2.0 and 1x USB 3.0. Other connectivity ports include — 1x Satellite In (F-type female), 1x Antenna (RF) (female), 1x CI+ 1.4 and 1x Ethernet RJ45.
Wireless connectivity options on this TV include a 5Ghz Wi-Fi, 2.5 Ghz Wi-Fi, Wifi-Direct and Bluetooth 5.0.
Now, for audio, it is packaged with 2 x 7W speakers.
Now, coming to power usage, the TV consumes 49.44 Watts on average and 0.5 Watts on standby.
It supports a power outlet of 100 V - 120 V/50 Hz - 60 Hz.