Includes standard barrel shape knob. Ball style knob P/N EC53 also available separately. 

Vernier-Assist^TM Throttle Controls for Dual Carburetor 912/914 Series Rotax Engines 
Innovative design allows a neat, clean installation without a clunky splitter box

McFarlane invents a new type of vernier engine control

This new type of control has all the fine adjustment benefits of an old style push-button release vernier control, with the simplicity, responsiveness and jam-proof safety of a friction lock control.

• Light weight and compact behind the dash
• Good hand space around the knob 
• Safer - Our roller action cannot jam 
• US Patent No. US 8,485,057 B1
• Vernier-Assist Assembly Video

These light weight controls use a patented roller action and do not use a positive lock thread engagement. Coarse adjustments are made by pushing the knob inwards or pulling the knob outwards. Fine adjustments are made by rotating the knob clockwise or counterclockwise. For extreme conduit routing or heavy carburetor load installation, slight inward or outward assist pressure could be required during rotation.

• Super-smooth friction lock
• Quality all metal construction
• High temperature Teflon lined for smooth, consistent control
  (Cheapy controls with poly liners will not tolerate engine temperatures)
• Available in 4, 6, 8, 12 foot and custom lengths
  • Measured from panel fitting to end of conduit, wires extend 6 inches beyond conduit
  • Easily trimmed to length
• Includes P/N 6408 hardware kit
  • Versatile threaded conduit terminals for easy adjustment (M6x1-6g x 1 inch thread)
  • Adjustable cable stops to limit travel
• Manufactured to the same quality standards as McFarlane's FAA-PMA parts

Specifications:

• Panel Fitting: 3/4-16 UNF x 0.875 inch thread
• Slip Fit Conduit Terminals: 2 each with M6x1-6g x 1 inch thread
• Conduit: 0.188 inch OD Teflon lined wound conduit
• Inner Wire: Heavy duty 0.062 inch diameter, 1x7 stainless steel twisted wire per MIL-DTL-87161
• Travel (stroke): 3.5 inch maximum
• Design Work Loads:
  • Push: Not applicable (designed for pull loads only)
  • Pull: 10 lbs maximum
• Typical Locking Force: 1 to 10 lbs (locking force dependent on friction lock engagement)
• Operating Temperature: -65 to 450 deg F

These controls are not for use on certified aircraft, or for flight controls or flight control trim tabs.
We currently offer these new controls for use on non-certified aircraft only. However, we plan to obtain FAA-PMA approval to offer the new Vernier-Assist mechanism as an option on many of our currently approved controls for Cessna and Piper, as well as our popular MC600 universal mixture control.