... 1. Style: Mini in-ear earphone, clip-on headphone, over-head headphone, noise cancelling headphone 2. Impendance: 300phms3. Magnet: Neodimium, Ferrite4. Spearker ... is a special inflight and travel products supplier with the mission to optimize the cost performance. The ... . The Optimization on function and weight, Optimization on function and environment cost, Optimization on function and budget, are ...