From Anarchy Online Wiki [AOWiki]

Ql stands for 'Quality Level' and is the level of an item or object. Quality Level has an effect on the statistics, values, and abilities of most items in the game. Quality Levels in the classic game range from 1 to 200. In Shadowlands some items with higher quality levels were introduced, many up to ql 300, a few up as high as 500. With the release of Alien Invasion many items were regularly made to range up to ql 300 instead of just ql 200. There is also a quality level of 'Special' that marks unique items or items that have their quality level hidden. Certain items like this show up with their true quality level when putting your inventory or backpack in which the item is stored into 'list' mode.