RFID tags are classified into three types based on whether or not they have a battery: active tags, passive tags, and semi-active tags. 1. Active RFID tags, which require their own transmitter and power supply, are less common. These tags are typically larger, more durable, and more expensive. 2. Semi-passive RFID tags are located directly between active and passive tags. The semi-passive tag functions exactly like the intermediate option and provides a number of features derived from the functionality of both active and passive tags. Semi-passive RFID tag characteristics include: Built-in battery, shorter read range than active tags but longer than passive tags. The dual frequency temperature sensing tags from OSRFID are semi-passive RFID tags. 3. The most common type of RFID tag is passive; it does not require a direct line of sight to the reader, but it has a shorter read range, is smaller in size, and weighs less. OSRFID is a Chinese RFID tag manufacturer specializing in passive RFID tags.