Optional heavy duty steel ball diff axle for the F1Ultra.

1 piece shaft for maximum durability that also provides extra rear weight (shafts weighs 26gr) for more traction in low grip conditions.

The shaft is solid on the right side and hollowed on the left side to help balance the rear pod.

Alloy diff ring mount that's a direct fit for the F1Ultra stock ball diff.

Not compatible with Xray F1 etc.

$29.95 MSRP.