A modular connection system (10/110) for connecting two pieces of telecommunications equipment (12/112) so as to prevent relative sliding between the two pieces of telecommunications equipment (12/112) and relative separation between the two pieces of telecommunications equipment (12/112) that is in a direction generally perpendicular to the direction of the relative sliding, the connection system (10/110) comprising: an interface structure to be positioned between the two pieces of telecommunications equipment (12/112), the interface structure defining a body with opposed faces (54, 56) and a stud on each face (54, 56), the stud defining a stem portion and a flange portion having a larger profile than the stem portion; a first piece of telecommunications equipment (12/112); a first slot positioned at a first surface of the first piece of telecommunications equipment (12/112), the first slot defining a receiver portion and a retention portion, wherein the receiver portion is sized to accommodate the flange portion of the stud of the interface structure and the retention portion is sized to accommodate the stem portion but not the flange portion of the stud; a second slot positioned at a second opposing surface of the first piece of telecommunications equipment (12/112), the second slot defining a receiver portion and a retention portion, wherein the receiver portion is sized to accommodate the flange portion of the stud of the interface structure and the retention portion is sized to accommodate the stem but not the flange portion of the stud; a first flexible cantilever positioned at the first surface of the first piece of telecommunications equipment (12/112) and a second flexible cantilever (48/148) positioned at the second opposing surface of the first piece of telecommunications equipment (12/112), each of the first and second cantilevers (40, 48/148) configured to abut a stud to prevent relative sliding between the interface structure and the first piece of telecommunications equipment (12/112); and a cantilever release (42/142) for at least the first cantilever, wherein at least a portion of the cantilever release (42/142) protrudes through the second surface so as to be able to flexibly move the first cantilever out of the way of a stud from an exterior of the second surface to enable slidable movement between the first piece of telecommunications equipment (12/112) and the interface structure mounted to the first surface of the first piece of telecommunications equipment (12/112) via the first slot. an interface structure to be positioned between the two pieces of telecommunications equipment (12/112), the interface structure defining a body with opposed faces (54, 56) and a stud on each face (54, 56), the stud defining a stem portion and a flange portion having a larger profile than the stem portion; a first piece of telecommunications equipment (12/112); a first slot positioned at a first surface of the first piece of telecommunications equipment (12/112), the first slot defining a receiver portion and a retention portion, wherein the receiver portion is sized to accommodate the flange portion of the stud of the interface structure and the retention portion is sized to accommodate the stem portion but not the flange portion of the stud; a second slot positioned at a second opposing surface of the first piece of telecommunications equipment (12/112), the second slot defining a receiver portion and a retention portion, wherein the receiver portion is sized to accommodate the flange portion of the stud of the interface structure and the retention portion is sized to accommodate the stem but not the flange portion of the stud; a first flexible cantilever positioned at the first surface of the first piece of telecommunications equipment (12/112) and a second flexible cantilever (48/148) positioned at the second opposing surface of the first piece of telecommunications equipment (12/112), each of the first and second cantilevers (40, 48/148) configured to abut a stud to prevent relative sliding between the interface structure and the first piece of telecommunications equipment (12/112); and a cantilever release (42/142) for at least the first cantilever, wherein at least a portion of the cantilever release (42/142) protrudes through the second surface so as to be able to flexibly move the first cantilever out of the way of a stud from an exterior of the second surface to enable slidable movement between the first piece of telecommunications equipment (12/112) and the interface structure mounted to the first surface of the first piece of telecommunications equipment (12/112) via the first slot.