An RFID reader is configured to be worn on the arm of a user and includes a housing with a bottom surface for facing the arm of a user and a top surface facing away from the arm. A securement structure engages the arm of the user to secure the housing. An antenna is mounted within the housing and is angled with respect to the bottom surface of the housing for providing an RF field at an angle to the arm of a user to direct the RF field toward an item held by the arm. The antenna includes an indexing structure with multiple angular positions for orientation of the antenna. A key structure is positioned in the housing and configured for engaging the indexing structure at an angular position around the antenna to orient the antenna at a desired rotational orientation in the housing to tune the antenna. Grip structures are formed along the top surface of the housing for gripping an item held by a user that contains an RFID tag that is read by the RFID reader.