A spinal disk implant comprises a solid body having four faces arranged to define a right-rectangular solid body and two faces that define the ends of the solid body. The faces that define the right-rectangular body include two opposed side faces and two opposed transverse faces. A kit that may be used by a surgeon includes an implant and an implant delivery tool dimensioned to releasably hold the implant. The delivery tool preferably has an implant holder with a pair of flexible opposed arms extending from a base, separated so that the implant can fit between the arms. Optionally, the implant holder may have a breakable release band extending around the implant to hold it in place until a weak link in the release band is intentionally broken during implantation.