A 165Hz gaming monitor redraws the image 165 times per second. Against a standard 60Hz office display the difference is large: motion looks smoother, fast camera turns look less smeared, and the display keeps up with a graphics card that can deliver high frame rates. Against a 144Hz display the difference is smaller, and most buyers will notice the size and resolution choice more than the step from 144Hz to 165Hz.
The evidenced gaming line on this site, models ZE215, ZG24E and ZG27F, offers both 144Hz and 165Hz, in 21.5, 24, 27 and 32 inch sizes with 1920 by 1080 and 2560 by 1440 resolutions. The product page for that line is the place to confirm which size and resolution combinations carry which refresh rate, because the line covers several sizes and the detailed sheet for each size was not recorded separately.
A buyer should also check the graphics card. A 165Hz display only shows its advantage when the computer can deliver frame rates near 165 frames per second in the games played. A card that delivers 60 frames per second will not look different on a 165Hz display, and the money may be better spent on size or resolution. State the games and the graphics card in an enquiry if the refresh rate choice is uncertain.
Order quantity and lead time are confirmed per model in enquiry, and prices are not published on this site.