is excellent for vacuuming line sets, removing all valve cores and valve core depressors. Reaches up to 1000 microns in minutes. without these. I bought two. A notice; You will not get any readings or subcooling after you prime the system with the tool installed, you must install the valve core, remove the valve core tool and reinsert the valve core pushers into the hose guides before installing the hoses (or purchase a second set). the system. I use a field instrument 480. I didn't want to buy