Air Locker 20 Gauge 5/8" Long T50 Fine Wire Stapler Kit, U641K. Upholstery Stapler is an easy to use pneumatic stapler with plenty of useful features. It uses standard 20-gauge T50 fine wire staples to get the job done right. The high-capacity bottom-load magazine handles 100 staples. The U641 stapler requires 60-100 PSI air pressure, so it will work with most air compressors. Comes in a Blow Molded Case. Kit includes 1/4", 3/8", 1/2" & 5/8" T50 3/8" crown staples each of 1000/Pack.