Polmac presents the Cup Key to put up and remove spraying nozzles on the booms spraying pesticides. The nozzle is currently fit and removed from the nozzle-holder by hand with big difficulty. Without the use of any protective device, injuries to fingers and the certain contact with chemical products are to be risked, while the help of gloves doesn’t assure any handiness, due to the small size of the nozzle and the narrow space of the structure (spraying boom) on which they are mounted. For fitting on the nozzle-holder, the nozzle with bayonet connection has to be inserted into the Cup Key and a 45° circular move has to be effected up to the locking of the nozzle. The removal procedure is carried out following the reversed operation. At the end of these operations the Cup Key has to be removed to be used afterwards.