Inductosyns work using the same basic physics as a transformer using planner arrays of inductive windings. Inductosyns typically require electrical connections to both the moving and stationary elements of the sensor. Inductosyn are uncommon due to high price and ITAR restrictions. New generation inductive sensors, such as IncOders from Zettlex are seen as a suitable alternative to Inductosyn. IncOders feature fully integrated electronics so they carry out a range of Built-In-Tests to check condition and produce error signals in the event of malfunction. Zettlex inductive angle encoders have no ITAR restrictions and typically require no export licence.