NEW YORK (AP) — All models of Onewheel self-balancing electric skateboards are under recall after at least four deaths and multiple injuries were reported in recent years, federal regulators say.

The 300,000 now-recalled skateboards, manufactured by Future Motion, can stop balancing a rider if the boards’ limits are exceeded — which risks serious crashes, according to the U.S. Consumer Product Safety Commission.

To address the crash hazard, a new safety alert feature called “haptic buzz” will be available through a firmware update for Onewheel GT, Pint X, Pint and XR boards in the coming weeks, Future Motion’s Onewheel team said.

Original Onewheel and Onewheel+ boards are not eligible for the firmware update — so eligble riders can arrange to receive a prorated refund in the form of store credit.