File:Koster UP 210.jpg

From DiscoverLiveSteam.com, 2013:

Koster GP7 1.5" scale, 7.5" gauge locomotive, all steel body held on by 2 nuts, removable in one piece. Four deep cycle batteries in series power a Curtis controller, (24 vdc) and are accessible through roof hatches for easy maintenance. Hand held control consists of master switch, horn button, bell button, reversing switch, light switch and run 1-8 throttle. Each axle is powered by 7500 rpm motors with gear boxes which move this locomotive at 15 mph clocked by radar. Approx. weight is 600 lbs. Also included are extra motors, wheels, axles gearboxes, and brake castings. Trucks are sprung and made out of cast aluminum. Built by Bill Koster about 20 years ago.