Composition: RFID nti + copper coil Frequency: LF 125KHz or 134.2KHz/HF 13.56MHz Suitable for chips: EM4102, TK4100, M150 S50, FM11RF08, NTAG213, etc Size: custom size, minimum diameter up to 4mm Notice: JavaScript yuav tsum tau rau cov ntsiab lus no.