A 2K gaming monitor shows 2560 by 1440 pixels, which is sharper than the 1920 by 1080 of a standard full high definition display. Text looks crisper, distant detail in a game looks clearer, and a desktop holds more windows side by side. The cost is graphics performance: the card must draw more pixels per frame, so frame rates fall unless the card is strong enough.
The evidenced gaming line on this site, models ZE215, ZG24E and ZG27F, offers 2560 by 1440 alongside 1920 by 1080, with 144Hz and 165Hz refresh rates and sizes from 21.5 to 32 inches. The product page records those resolutions for the line, and a buyer should confirm the resolution for a particular size in an enquiry, because the line covers several sizes and each size's detailed sheet was not recorded separately.
As a rule, 2K suits larger gaming displays, where the extra pixels are visible, and stronger graphics cards, which can hold high frame rates at the higher resolution. On a small display or with a modest card, 1080p often gives a smoother experience. State the display size and the graphics card in an enquiry if the resolution choice is uncertain.
Order quantity and lead time are confirmed per model in enquiry, and prices are not published on this site.