Hi George,
The Louisville Slugger Pitching Machine Screen has a 20 inch tall, 12 inch wide opening allowing for minor pitching machine alignment adjustments. The bottom of the opening is approximately 18 inches from the ground, which puts the top of the hole at 38 inches above the ground.
The Rawlings Pro Line 3 Wheel pitching machine has a softball release point of 32 inches, so it would work for that. The baseball release point is at 60 inches, so it definitely will not work for baseball with this machine.
Most people purchase the Cimarron Residential L-Screen. It is much better built with extremely tough #42 netting and will definitely work with this pitching machine or live pitchers.