It has a small diameter air tube to access into holes down to 1/8" diameter, a 1/4" NPT air inlet and a maximum operating pressure of 120 PSI.The most effective blind hole air gun available, it is ideal for both deep crevices and blind holes. This air gun is 100% effective in delivering a high velocity jet of air to flush out chips and dirt. Safety air shield provides effective chip-guarding as required by OSHA. Pistol grip casting and angled extension make this light weight air gun easy to handle. It has a 4" straight extension and a 2" extension after the 45 degree bend.