A shoulder prosthesis kit comprising: a first metaglene component including (i) a first body defining an outer diameter, (ii) a first augment extending medially from the first body, and (iii) a first void defined by a portion of the first body and a portion of the first augment, and a bearing component defining a cavity configured to couple with the first body, and having a bearing surface, in which: (a) at least one first fastener hole (145A, 145B, 145C) extends from the first void through the first augment, (b) at least one second fastener hole (137A, 137B, 137C, 137D) extends through the body, and (c) a first (145B, 145C) of the at least one first fastener holes extends through the first augment at an angle which is different from that of a second of the at least one first fastener holes and also different from the angle at which the at least one second fastener holes extend through the body so that the first of the first fastener holes does not align with any of the at least one second fastener holes, characterised in that the kit includes a plurality of bearing components, each of the plurality of bearing components defining a cavity configured to couple with the first body, and having a bearing surface that is sized differently from the size of another of the plurality of bearing components, and the second of the at least one first fastener holes is aligned with a first of the at least one second fastener holes so that a fastener can extend through the said aligned holes without changing angle. a first metaglene component including (i) a first body defining an outer diameter, (ii) a first augment extending medially from the first body, and (iii) a first void defined by a portion of the first body and a portion of the first augment, and a bearing component defining a cavity configured to couple with the first body, and having a bearing surface, in which: (a) at least one first fastener hole (145A, 145B, 145C) extends from the first void through the first augment, (b) at least one second fastener hole (137A, 137B, 137C, 137D) extends through the body, and (c) a first (145B, 145C) of the at least one first fastener holes extends through the first augment at an angle which is different from that of a second of the at least one first fastener holes and also different from the angle at which the at least one second fastener holes extend through the body so that the first of the first fastener holes does not align with any of the at least one second fastener holes, (a) at least one first fastener hole (145A, 145B, 145C) extends from the first void through the first augment, (b) at least one second fastener hole (137A, 137B, 137C, 137D) extends through the body, and (c) a first (145B, 145C) of the at least one first fastener holes extends through the first augment at an angle which is different from that of a second of the at least one first fastener holes and also different from the angle at which the at least one second fastener holes extend through the body so that the first of the first fastener holes does not align with any of the at least one second fastener holes, characterised in that the kit includes a plurality of bearing components, each of the plurality of bearing components defining a cavity configured to couple with the first body, and having a bearing surface that is sized differently from the size of another of the plurality of bearing components, and the second of the at least one first fastener holes is aligned with a first of the at least one second fastener holes so that a fastener can extend through the said aligned holes without changing angle.