Abstract: Section insulator for rigid catenary which has a dual functionality, since it can exercise the functions both of conventional section insulator and of neutral section insulator, configured so that it maintains a mechanical continuity which allows the smooth passage of the pantograph, minimizing the requirement for adjustment and maintenance. The insulator basically comprises a pair of conductor rail segments (2) between which is disposed a single central shoe (1) obliquely disposed with respect to the direction of the catenary, a pair of spark wires (9) wherein the electric field is broken and a series of strips (8) disposed on said central shoe (1) which, together with a bridging cable which extends from them to the conductor rail segment (2), enables bridging the wire conductor of the insulator (3) when one want to maintain the power supply to the pantograph.