Deck spring (cushion) used on Star Trac treadmill models: TR3900, TR4000, TR4500, TR5500 (PRO S), TR5600 (PRO).

NOTE: Not all TR3900 & TR4000 used this cushion, some of them used a 2 piece system. This is for use on one side of the machine. If you are wanting to replace the deck springs on both the left and right side of the deck, you will need to order two of these.

NOTE: These springs need to be glued to the treadmill frame we suggest you order 211000121 with this item.