The Acer 275HL has a maximum contrast ratio of 100000000:1. That's over five times the contrast ratio of a 20000000:1 PC monitor, which is the most common contrast ratio.
A 100000000:1 dynamic contrast ratio is actually the best contrast ratio across all medium monitors that have been around for a similar time to the 275HL.
Across comparable types of LCD screen the worst contrast ratio is Mega Contrast.
We think you might also be interested in some of the alternative PC monitors that have a 100000000:1 dynamic contrast ratio currently available including a cheaper PC monitor such as the Acer 276HL (£139.99), or the Asus VW24 (£185.07) or you might consider a higher rated PC monitor such as the Acer H276HL (£201.88).