A mid-turbine frame for a gas turbine engine, comprising: a bearing system including a bearing housing; a first tube defining an inner fluid passage configured to carry a first fluid to the bearing system; a second tube disposed around the first tube and defining an outer fluid passage between the first tube and the second tube, the outer fluid passage configured to carry a second fluid to the bearing system; a first fitting coupled to the bearing housing and to the first tube and the second tube; a first seal disposed between the bearing housing and the first fitting, characterised in that the mid-turbine frame further comprises: a third tube disposed around the second tube and defining a chamber between the second tube and the third tube; a second fitting coupling the second tube and the third tube to the bearing housing, the first fitting comprising: an inner portion fluidly coupled to the inner fluid passage and configured to carry the first fluid to the bearing system; and an outer portion disposed around the inner portion and fluidly coupled to the outer fluid passage, the outer portion configured to carry the second fluid to the bearing system, wherein the first fitting is configured to fluidly isolate the first fluid from the second fluid, the first seal is configured to maintain fluid isolation of the first fluid from the second fluid, and the mid-turbine frame further comprises a second seal and a third seal configured to provide a fluid-tight seal between the second fitting and the bearing housing wherein the chamber is configured to contain the fluid with the third tube in the event that there is a fluid leak from first tube and/or second tube. a bearing system including a bearing housing; a first tube defining an inner fluid passage configured to carry a first fluid to the bearing system; a second tube disposed around the first tube and defining an outer fluid passage between the first tube and the second tube, the outer fluid passage configured to carry a second fluid to the bearing system; a first fitting coupled to the bearing housing and to the first tube and the second tube; a first seal disposed between the bearing housing and the first fitting, characterised in that the mid-turbine frame further comprises: a third tube disposed around the second tube and defining a chamber between the second tube and the third tube; a second fitting coupling the second tube and the third tube to the bearing housing, the first fitting comprising: an inner portion fluidly coupled to the inner fluid passage and configured to carry the first fluid to the bearing system; and an outer portion disposed around the inner portion and fluidly coupled to the outer fluid passage, the outer portion configured to carry the second fluid to the bearing system, wherein the first fitting is configured to fluidly isolate the first fluid from the second fluid, the first seal is configured to maintain fluid isolation of the first fluid from the second fluid, and the mid-turbine frame further comprises a second seal and a third seal configured to provide a fluid-tight seal between the second fitting and the bearing housing wherein the chamber is configured to contain the fluid with the third tube in the event that there is a fluid leak from first tube and/or second tube. a third tube disposed around the second tube and defining a chamber between the second tube and the third tube; a second fitting coupling the second tube and the third tube to the bearing housing, the first fitting comprising: an inner portion fluidly coupled to the inner fluid passage and configured to carry the first fluid to the bearing system; and an outer portion disposed around the inner portion and fluidly coupled to the outer fluid passage, the outer portion configured to carry the second fluid to the bearing system, wherein the first fitting is configured to fluidly isolate the first fluid from the second fluid, the first seal is configured to maintain fluid isolation of the first fluid from the second fluid, and the mid-turbine frame further comprises a second seal and a third seal configured to provide a fluid-tight seal between the second fitting and the bearing housing wherein the chamber is configured to contain the fluid with the third tube in the event that there is a fluid leak from first tube and/or second tube. an inner portion fluidly coupled to the inner fluid passage and configured to carry the first fluid to the bearing system; and an outer portion disposed around the inner portion and fluidly coupled to the outer fluid passage, the outer portion configured to carry the second fluid to the bearing system, wherein the first fitting is configured to fluidly isolate the first fluid from the second fluid, the first seal is configured to maintain fluid isolation of the first fluid from the second fluid, and the mid-turbine frame further comprises a second seal and a third seal configured to provide a fluid-tight seal between the second fitting and the bearing housing wherein the chamber is configured to contain the fluid with the third tube in the event that there is a fluid leak from first tube and/or second tube.