An apparatus configured to be installed in a vehicle comprising: an impact absorbing portion that is part of an apparatus main body ; and a support member to which the impact absorbing portion is fixed, wherein the apparatus comprises: an opposing fixing member , a fastening member that fastens the support member and the opposing fixing member together, and an opening in the impact absorbing portion in which the fastening member is inserted; characterized in that the support member and the opposing fixing member are fastened together by the fastening member , with the impact absorbing portion disposed between the support member and the opposing fixing member ; a moving clearance (δ) provided in an impact acting direction between the opening and the fastening member ; a protrusion provided on one of the opposing fixing member and the impact absorbing portion , and a recess provided in another of the opposing fixing member and the impact absorbing portion , or a protrusion provided on one of the support member and the impact absorbing portion , and a recess provided in another of the support member and the impact absorbing portion ; the protrusion and the recess are configured to be fitted to position the impact absorbing portion and the support member in the impact acting direction; and the protrusion is configured to be separated when a shearing force in the impact acting direction acts on the protrusion . an impact absorbing portion that is part of an apparatus main body ; and a support member to which the impact absorbing portion is fixed, wherein the apparatus comprises: an opposing fixing member , a fastening member that fastens the support member and the opposing fixing member together, and an opening in the impact absorbing portion in which the fastening member is inserted; characterized in that the support member and the opposing fixing member are fastened together by the fastening member , with the impact absorbing portion disposed between the support member and the opposing fixing member ; a moving clearance (δ) provided in an impact acting direction between the opening and the fastening member ; a protrusion provided on one of the opposing fixing member and the impact absorbing portion , and a recess provided in another of the opposing fixing member and the impact absorbing portion , or a protrusion provided on one of the support member and the impact absorbing portion , and a recess provided in another of the support member and the impact absorbing portion ; the protrusion and the recess are configured to be fitted to position the impact absorbing portion and the support member in the impact acting direction; and the protrusion is configured to be separated when a shearing force in the impact acting direction acts on the protrusion . an opposing fixing member , a fastening member that fastens the support member and the opposing fixing member together, and an opening in the impact absorbing portion in which the fastening member is inserted; characterized in that the support member and the opposing fixing member are fastened together by the fastening member , with the impact absorbing portion disposed between the support member and the opposing fixing member ; a moving clearance (δ) provided in an impact acting direction between the opening and the fastening member ; a protrusion provided on one of the opposing fixing member and the impact absorbing portion , and a recess provided in another of the opposing fixing member and the impact absorbing portion , or a protrusion provided on one of the support member and the impact absorbing portion , and a recess provided in another of the support member and the impact absorbing portion ; the protrusion and the recess are configured to be fitted to position the impact absorbing portion and the support member in the impact acting direction; and the protrusion is configured to be separated when a shearing force in the impact acting direction acts on the protrusion . <EOS>