AT = All Terrain, wh = wide handle. Fitted with custom wheels that absorb shocks on a bumpy, uneven athletic fields and extra axle ball bearing that make it roll smoother and more straight for easy line striping. Specially designed wide handle ( WH ) for stability of the machine during striping to help get a straighter line and more control during striping application. Applicator can rest both hands on the machines that helps reducing user fatigue. All metal construction, sturdy, durable, easy to set-up, easy to clean-up and store. ATwh aerosol paint marking line striping machine is ideal for painting, striping, line marking of football, soccer, lacrosse, baseball and field hockey athletic fields. It ships in a compact cardboard box, just unpack, unfold the spray handle and firm it up by tightening the installed wing nuts. To use, shake the aerosol can thoroughly as per label instructions and install the paint can in the horse-shoe type can holder on the ATwh machine. Adjust the tension on the cable, if needed, by using an adjustable screw underneath the handle trigger. Line spray width can be adjusted by lowering or raising the two wing nuts attached to the side of the can holder. For sharp looking lines make sure the inverted aerosol can spray pattern is not obstructed by any part of the machine. To clean up any over spray, let it dry and then easily scrape it off, then store machine. We have a GPS-AFLS ( GPS based athletic field layout system ) to help with the layout of your athletic fields.