20-2106 Early Premier SD45 (not available in non-powered) PS1 or horn only.
20-2915 Re-tooled Premier SD45 (available in PS2 or non-powered)
30-20419 Scaleking SD45 (Same as Early Premier SD45, but improved with scale fuel tank and painted handrails). Available in PS3 or non-powered. MTH refers to these as Railking Scale.
30-2360 Scaleking SD45 (Same as Early Premier SD45, but improved with scale fuel tank and painted handrails). Available in PS2 or non-powered. MTH refers to these as Railking Scale.
30-2152 Is the Shorty (027 style) SD45.