These cards works in the 125 kHz RF range. These cards come out with a unique 32-bit ID and are not re-programmable. These EM4001 also know as GK4001 or TK4001 tag and also compatible with EM4102 cards.
Rotelco Communication Systems established in 2003 as a PABX Solution provider has been an authorized distributor for ZKTECO Co., Ltd since 2012 making it as one of the oldest authorized distributors in Sri Lanka.
