... . Ceramic material, Small and light but very strong. Smart heart with small appearance: Impinj chip bulit-in, Alien chips optioanl ... . 2 times reading distance than regular anti-metal tagPassive card design, ... .12 (inch) Frequency902-928MHz, Optional as requestWeight3.8gRead Rangeup to 2.0 (m) / 6 (feet) (ERP 2W)On Metal or BalancedOn ...