The Sutphen SLR 75 Rear-Mount Aerial Ladder. It’s the first in a new generation of Sutphen Aerials, and it’s everything you’ve come to expect from Sutphen. The new SLR 75 features a short maneuverable wheelbase, low overall travel height, pump options from 1500-2000 gpm, water tank capacity of 300-500 gallons, and over 200 cu. ft. of compartment space. With functionality of a rescue pumper and the versatility of a ladder, the SLR 75 will be the workhorse of your fleet.