The K-4s were the most outstandingly successful and recognized class of locomotives on the Pennsylvania Railroad. 425 units were built from 1914 to 1928 and were numbered in random order (a Pennsy practice) from #8 to #8378. Serving through both World Wars and beyond, even the modern Duplexes did not replace them as the mainline steam passenger engines.

Features:

• Die cast body with heavy die cast chassis for max. tractive effort
  
• Paragon3 with Rolling Thunder DCC w/Sound (Rolling Thunder transmitter onboard)
  
• Integral DCC Decoder with Back EMF for DC and DCC
  
• Precision drive mechanism engineered for continuous heavy load towing and smooth slow speed operation
  
• Powerful can motor
  
• Synchronized puffing smoke with chuff sound
  
• Variable puffing smoke intensity and timing
  
• Sharp painting with authentic paint schemes
  
• Prototypical light operation with golden white LED headlight, rear light
  
• Operating metal knuckle couplers
  
• Factory Installed engineer and fireman figures
  
• Separately applied handrails, ladders, whistle, and brass bell
  
• Will operate on Code 70, 83 and 100 rail
  
• Minimum radius: 18" radius or greater recommended
• Operates in DC & DCC (use DCMaster for DC sound)
  
  • 2 Selectable Bells
    
  • 3 playable whistles with variable endings
    
  • 1 long, non-looped whistle
    
  • 1 alternate whistle for locomotives with a second horn
    Quill whistle with Digitrax DT400 or NCE Pro Cab throttle
    
• 4 Times Expanded Autopilot storage
  
• Expanded Startup and Shutdown sequences
  
• Smoke Temperature safety cutoff sensor
  
• 2 Watt Audio output
  
• 90 db signal to noise ratio
  
• 16 bit audio resolution
  
• 24 sounds with separate volume control
  
• Unmatched frequency response as low as 20 Hz when paired with Rolling Thunder subwoofer kit
  
• 8 simultaneously playable audio channels
  
• Improved motor control in DC and DCC
  
• Motor short circuit protection
  
• Outputs for headlights, MARS lights, automatic cab light, rear lights, marker lights, ditch lights, firebox light, running board lights, number board lights and a few spares