Annuloplasty device for implantation adjacent an annulus of a tricuspid valve, the annulus comprising anterior, posterior and septal aspects adjacent anterior, posterior and septal leaflets, respectively, of the tricuspid valve, the device comprising: a ring body comprising: an anterior portion, a posterior portion and a septal portion shaped to conform to, and for implantation adjacent, the anterior, posterior and septal aspects of the annulus, respectively; and first and second end portions that are more flexible than a remainder of the ring body to provide a gradual transition from the remainder of the ring body to tissue of the tricuspid valve annulus; wherein the ring body is curvilinear, with substantially no flat portions, and forming a shape. Related devices, kits and sizer devices.