A device comprising: a catheter comprising: a catheter body; and an expandable balloon positioned on the catheter body; and a splittable sheath (12,70,120,160) comprising: a sheath body (14,74,122) defining a lumen (18,78,128) configured to receive the expandable balloon; and a tab (16A,16B,90A,90B,162) extending from a proximal end (22,82,132) or a distal end (20,80,130) of the sheath body (14,74,122), wherein outward movement of the tab (16A,16B,90A,90B,162) relative to a central longitudinal axis (26,86,121) of the sheath body (14,74,122) causes splitting of the sheath body (14,74,122), wherein the tab (16A,16B,90A,90B,162) includes a major surface (17A,17B,92A,92B,164) having an outer edge (19A,19B,92A,92B,166) defining a serpentine shape, wherein the outer edge (19A,19B,92A,92B,166) of the major surface (17A,17B) includes alternating outwardly-projecting portions and inwardly projecting portions, each outwardly-projecting portion extending outwardly in an x-axis direction from the central longitudinal axis (26,86,121) of the sheath body (14,74,122) compared to the inwardly projecting portions, wherein the x-axis is perpendicular to a z-axis along which the thickness (T S) of the tab (16A,16B,90A,90B,162) is measured. a catheter body; and an expandable balloon positioned on the catheter body; and a splittable sheath (12,70,120,160) comprising: a sheath body (14,74,122) defining a lumen (18,78,128) configured to receive the expandable balloon; and a tab (16A,16B,90A,90B,162) extending from a proximal end (22,82,132) or a distal end (20,80,130) of the sheath body (14,74,122), wherein outward movement of the tab (16A,16B,90A,90B,162) relative to a central longitudinal axis (26,86,121) of the sheath body (14,74,122) causes splitting of the sheath body (14,74,122), wherein the tab (16A,16B,90A,90B,162) includes a major surface (17A,17B,92A,92B,164) having an outer edge (19A,19B,92A,92B,166) defining a serpentine shape, wherein the outer edge (19A,19B,92A,92B,166) of the major surface (17A,17B) includes alternating outwardly-projecting portions and inwardly projecting portions, each outwardly-projecting portion extending outwardly in an x-axis direction from the central longitudinal axis (26,86,121) of the sheath body (14,74,122) compared to the inwardly projecting portions, wherein the x-axis is perpendicular to a z-axis along which the thickness (T S) of the tab (16A,16B,90A,90B,162) is measured. a sheath body (14,74,122) defining a lumen (18,78,128) configured to receive the expandable balloon; and a tab (16A,16B,90A,90B,162) extending from a proximal end (22,82,132) or a distal end (20,80,130) of the sheath body (14,74,122), wherein outward movement of the tab (16A,16B,90A,90B,162) relative to a central longitudinal axis (26,86,121) of the sheath body (14,74,122) causes splitting of the sheath body (14,74,122), wherein the tab (16A,16B,90A,90B,162) includes a major surface (17A,17B,92A,92B,164) having an outer edge (19A,19B,92A,92B,166) defining a serpentine shape, wherein the outer edge (19A,19B,92A,92B,166) of the major surface (17A,17B) includes alternating outwardly-projecting portions and inwardly projecting portions, each outwardly-projecting portion extending outwardly in an x-axis direction from the central longitudinal axis (26,86,121) of the sheath body (14,74,122) compared to the inwardly projecting portions, wherein the x-axis is perpendicular to a z-axis along which the thickness (T S) of the tab (16A,16B,90A,90B,162) is measured.