The invention relates to an agricultural implement for spreading a pumpable medium, with a support frame connectable to a vehicle and at least one first spreader arm provided with outlets for pumpable medium. The spreader arm can be folded outward to a position transversely of the direction of travel of the vehicle. The invention further relates to a conversion kit for improving existing agricultural implements, to a vehicle provided with such an agricultural implement, and to a method for making the agricultural implement ready for use.