This study includes the placement of two implants in the interforaminal area of the mandible then the cases are divided randomly into two groups: in the first group; each patient received two ball and socket attachments and in the second group; each patient received two GPS attachments then the pickup procedure of the overdenture is done followed by measurement of retention using digital Forcemeter. The measurement of retention indicated that the GPS attachments have higher retentive values than the ball and socket attachments.