Pump comprising: - a pump body in which it is possible to identify a suctioning mouth and a delivery mouth; - a delivery head connected to said pump body and in which said delivery mouth is obtained; - a tubular jacket arranged inside said pump body and configured to contain an electric motor and a pumping unit connected through a transmission shaft; - a sealing unit arranged inside said tubular jacket between said electric motor and said pumping unit to delimit a motor housing containing said electric motor and a pumping housing containing said pumping unit; - a cover applied on said tubular jacket and comprised between said delivery head and said electric motor; - an annular body comprised between said cover and said delivery head to delimit a delivery chamber communicating with said delivery mouth; - a tubular interspace defined between said pump body and said tubular jacket; - a plurality of first flow ways made in said tubular jacket and configured to place said pumping housing in communication with said tubular interspace; - a plurality of second flow ways made in said annular body and configured to place said delivery chamber in communication with said tubular interspace, characterised in that in said annular body there are: - first connection means configured to axially constrain said annular body and said cover to each other and comprising a first annular edge projecting towards the inside of said annular body, said first annular edge being configured to be arranged to cover a corresponding perimeter edge of said cover arranged at the level of said tubular jacket, and - second connection means configured to axially constrain said annular body and said delivery head to each other and comprising a second annular edge projecting towards the outside of said annular body, said second annular edge having a substantially U-shaped profile which identifies a concavity facing towards said tubular interspace, said second annular edge being comprised between said cover, said pump body and said delivery head, said second annular edge being provided with through holes configured to receive means for fixing said second annular edge to said delivery head. - a pump body in which it is possible to identify a suctioning mouth and a delivery mouth; - a delivery head connected to said pump body and in which said delivery mouth is obtained; - a tubular jacket arranged inside said pump body and configured to contain an electric motor and a pumping unit connected through a transmission shaft; - a sealing unit arranged inside said tubular jacket between said electric motor and said pumping unit to delimit a motor housing containing said electric motor and a pumping housing containing said pumping unit; - a cover applied on said tubular jacket and comprised between said delivery head and said electric motor; - an annular body comprised between said cover and said delivery head to delimit a delivery chamber communicating with said delivery mouth; - a tubular interspace defined between said pump body and said tubular jacket; - a plurality of first flow ways made in said tubular jacket and configured to place said pumping housing in communication with said tubular interspace; - a plurality of second flow ways made in said annular body and configured to place said delivery chamber in communication with said tubular interspace, - first connection means configured to axially constrain said annular body and said cover to each other and comprising a first annular edge projecting towards the inside of said annular body, said first annular edge being configured to be arranged to cover a corresponding perimeter edge of said cover arranged at the level of said tubular jacket, and - second connection means configured to axially constrain said annular body and said delivery head to each other and comprising a second annular edge projecting towards the outside of said annular body, said second annular edge having a substantially U-shaped profile which identifies a concavity facing towards said tubular interspace, said second annular edge being comprised between said cover, said pump body and said delivery head, said second annular edge being provided with through holes configured to receive means for fixing said second annular edge to said delivery head.