Reduce the force required to open your lever and cycle the bolt by reducing the force of the spring acting on the hammer without sacrificing consistent primer strikes and ignition, ease of cycling is going to provide quicker follow up shots while maintaining a steady aim on your target, and less finger fatigue after a long day on the range.
 
Fit's Marlin Models 39a, 1894, 1895, 336 and 444 models.
 
*Photo is representative and may not reflect the exact item.*