This free elements case includes dog bones and axles the TT-01 chassis. It includes 2 long and 2 short axles. The fast axles are used the front side of TT-01, that may provide the TT-01 a track width of 185mm. The long axles are used the backside regarding the TT-01, that may provide you with the TT-01 a track width of 190mm. Note: you will need the long axles only if you are using a body set including a wider straight back tract/width. Example: The Ferrari Enzo additionally the Porsche 911 have a wider rear track, consequently long back axles are acclimatized to widen a corner associated with the TT-01 to make certain a true determine look. When utilizing Tamiya body sets which may be 185mm wide for both front and rear just utilize the front axles as replacements or purchase item 9005713, which include 4 fast axles.