A hinge installable on a hinged door, preferably of a shower cabin, comprising: - a primary body installable at a recess obtained along an edge of a hinged door, said primary body extending along a longitudinal direction along which a lower groove and an upper groove are obtained so that said primary body has a substantially "H"-shaped cross section, said lower groove being shaped to couple with a portion of the hinged door in which the recess is present so that said primary body abuts against both surfaces of the hinged door; - a secondary body insertable in said upper groove and having a width and height equal to or less than those of said upper groove and a depth at most equal to that of said upper groove, said depth being a dimension transverse to a pair of side portions of said primary body, said secondary body having a longitudinal extension less than that of said upper groove so as to be slidably movable within said upper groove along said longitudinal direction to allow the adjustment of the orientation and extension of the hinged door, said secondary body having a hole obtained on an opposite upper surface, in use, to said upper groove and adapted to receive a rotating pin for the opening and closing movement of the hinged door; - at least one locking element interposable between said primary body and said secondary body and configurable at least in a constraint condition in which it maintains said secondary body in a static and stable position with respect to said primary body, characterised in that said primary body has a through side groove to allow the configuration of said at least one locking element between said constraint condition and a free condition in which said secondary body is slidably movable in said upper groove, said side groove being obtained on a side portion of the primary body and being in communication with said upper groove, said locking elements being arranged through said side groove to configure the secondary body in the constraint condition.. - a primary body installable at a recess obtained along an edge of a hinged door, said primary body extending along a longitudinal direction along which a lower groove and an upper groove are obtained so that said primary body has a substantially "H"-shaped cross section, said lower groove being shaped to couple with a portion of the hinged door in which the recess is present so that said primary body abuts against both surfaces of the hinged door; - a secondary body insertable in said upper groove and having a width and height equal to or less than those of said upper groove and a depth at most equal to that of said upper groove, said depth being a dimension transverse to a pair of side portions of said primary body, said secondary body having a longitudinal extension less than that of said upper groove so as to be slidably movable within said upper groove along said longitudinal direction to allow the adjustment of the orientation and extension of the hinged door, said secondary body having a hole obtained on an opposite upper surface, in use, to said upper groove and adapted to receive a rotating pin for the opening and closing movement of the hinged door; - at least one locking element interposable between said primary body and said secondary body and configurable at least in a constraint condition in which it maintains said secondary body in a static and stable position with respect to said primary body, characterised in that said primary body has a through side groove to allow the configuration of said at least one locking element between said constraint condition and a free condition in which said secondary body is slidably movable in said upper groove, said side groove being obtained on a side portion of the primary body and being in communication with said upper groove, said locking elements being arranged through said side groove to configure the secondary body in the constraint condition..