Touted as an attractive supplement to or replacement of traditional bar codes in a variety of applications, the MCRF355 and MCRF360 13.56-MHz RFID tagging devices are a pair of passive tag engines with advanced anticollision circuitry for reading multiple tags in the same reader field. This "cloaking" feature minimizes the detuning effect of adjacent tags. Other features include extremely low power consumption for extended read range and 154 bits of user memory. Both devices are contact-programmable and will primarily be used in write-once, read-many (WORM) applications. The MCRF355 allows the user to externally tune a resonance capacitor, while the MCRF360 contains an on-chip 100 pF resonance capacitor. Available in samples and volume production.