An apparatus for fastening around a cranial burr hole includes a substantially flat core and a shell encapsulating a ring portion of the core. The shell defines an orifice substantially centered within the ring portion, and has a contoured lower surface to match the cranial curvature. Pliable arms of the core extend laterally from the ring portion, each being terminated by a fastener member. A central portion of a placement tool for the apparatus has a lower part configured to extend through the apparatus orifice, and an upper part from which first and second arms of the tool extend laterally. Each tool arm is terminated with a receptacle to hold a bone screw, and, when the tool central portion lower part extends through the apparatus orifice, each receptacle aligns with a corresponding fastener member, and lower openings of the receptacles are generally oriented along the contoured lower surface.