Roll-over protection device and vehicle provided with the same

The roll bar for a ride-on lawn mower comprises vertical arms (44) attached to a U-shaped top (50) by pivots. These are made up of two bars (68) with ledges (60) at one end. The bars are mounted so they face each other with the ledges overlapping their ends. Each bar has a hole (70) for a pivot (74) and a second hole (72) for a locking pin (78). An Independent claim is included for a lawn, garden or ground maintenance vehicle fitted with the roll bar.