Airless Pressure Roller Cover / Nap 9 InchThese quality replacement naps are hard wearing and economical to replace. Three nap length options are available 1 2" , 3 4" (standard) , 1 1 4". Pressure rollering transforms your airless paint sprayer into a rolling system for increased versatility, I deal for applying paint efficiently in areas where spraying isn't suitable. Using a pressure roller is up to four times faster than a traditional roller while eliminating the mess of a roller tray.