Electrical connection jumper, of the screw type in particular for switchboard terminal blocks, extending in a longitudinal lengthwise direction (X-X), transverse widthwise direction (Y-Y) and vertical direction (Z-Z) perpendicular to the preceding directions, and comprising: - a conducting body comprising at least two sub-bodies, each substantially in the form of an overturned "U" having --) a respective head lying in a plane (X-Y) parallel to the longitudinal direction (X-X) and transverse direction (Y-Y) and --) respective contact plates lying in planes (X-Z) parallel to the longitudinal direction (X-X) and vertical direction (Z-Z) and situated opposite each other in the transverse direction (Y-Y) relative to the head; --) each head having a through-hole in the vertical direction (Z-Z); the at least two conducting sub-bodies being connected in the longitudinal direction (X-X) by means of a tongue; - an insulating body comprising at least two sub-bodies with a substantially parallelepiped shape, made of suitable insulating material and connected together longitudinally (X-X) by a vertical membrane of reduced thickness in the transverse direction (Y-Y); - at least two screws for performing fixing to a terminal block; characterized in that each insulating sub-body has, passing through it, a respective vertical through-hole; the insulating body has a plane for coupling with the conducting body, which coupling plane is parallel, in use, to the plane (X-Y) of the heads of the conducting bodies and comprises, between each sub-body and the adjacent sub-body, a pair of arched lugs situated opposite each other in the transverse direction (Y-Y) and extending in the longitudinal direction (X-X) so that respective vertical arms of the lugs are respectively connected to each one of the adjacent sub-bodies; each arched lug having a tooth extending in the transverse direction (Y-Y) towards the inside of the insulating body in the empty space between the two sub-bodies, said arched lug with tooth allowing relative reversible engagement of the insulating body and the conducting body; - each of the screws for performing fixing to a terminal block is suitable for insertion into the through-hole of a respective sub-body of the insulating sub-bodies and into the through-hole of a respective conducting sub-body of the conducting body. - a conducting body comprising at least two sub-bodies, each substantially in the form of an overturned "U" having --) a respective head lying in a plane (X-Y) parallel to the longitudinal direction (X-X) and transverse direction (Y-Y) and --) respective contact plates lying in planes (X-Z) parallel to the longitudinal direction (X-X) and vertical direction (Z-Z) and situated opposite each other in the transverse direction (Y-Y) relative to the head; --) each head having a through-hole in the vertical direction (Z-Z); --) a respective head lying in a plane (X-Y) parallel to the longitudinal direction (X-X) and transverse direction (Y-Y) and --) respective contact plates lying in planes (X-Z) parallel to the longitudinal direction (X-X) and vertical direction (Z-Z) and situated opposite each other in the transverse direction (Y-Y) relative to the head; --) each head having a through-hole in the vertical direction (Z-Z); - an insulating body comprising at least two sub-bodies with a substantially parallelepiped shape, made of suitable insulating material and connected together longitudinally (X-X) by a vertical membrane of reduced thickness in the transverse direction (Y-Y); - at least two screws for performing fixing to a terminal block; - each of the screws for performing fixing to a terminal block is suitable for insertion into the through-hole of a respective sub-body of the insulating sub-bodies and into the through-hole of a respective conducting sub-body of the conducting body.