An intervertebral implant for fusing vertebrae is disclosed. The implant may have a body with curved, posterior and anterior faces separated by two narrow implant ends, superior and inferior faces having a plurality of undulating surfaces for contacting vertebral endplates, and at least one depression in the anterior or posterior face for engagement by an insertion tool. The implant may also have one or more vertical through-channels extending through the implant from the superior face to the inferior face, a chamfer on the superior and inferior surfaces at one of the narrow implant ends, and/or a beveled edge along a perimeter of the superior and inferior faces. The implant configuration facilitates transforaminal insertion of the implant into a symmetric position about the midline of the spine so that a single implant provides balanced support to the spinal column. The implant may be formed of a plurality of interconnecting bodies assembled to form a single unit. An implantation kit and method are also disclosed.