Radio Frequency and Intermediate Frequency (RF/IF) products are used for wireless transmission of information by means of electromagnetic radiation. Radio Frequency Identification (RFID) is a specific subset of general RF applications, characterized by use of small, inexpensive devices known as "tags" capable of containing a limited amount of information, that can be wirelessly retrieved (and in some cases modified) through the use of a specialized device known as a "reader" and which are commonly used for object or material tracking, inventory, and similar purposes. Products found within this category may range from finished units for end use, to component-level products and materials from which such finished goods are assembled.