The Sanwa Denshi JLF-SP-Y Yellow Tension Spring adds "weight" to the Sanwa Denshi JLF and JLX joystick lever series. In a default JLF/JLX joystick lever, it needs 1N force to move and compress the spring. The half size of the yellow spring allows the lever to start the initial movement with 1.3N force and ends in the final compression with 2N force. This stiffer spring aims to replicate dampening feeling of rubber grommets found in Koren-style joystick levers.