Xiaomi ZBW4326TY Professional Store Hybrid Dual Mi Hybrid Earphone in-Ear Headphones Multi-Unit Circle Iron Mixed Piston Earphones, Silver Dual sound unit, more musical detail, 20 step to build metal sound chamber Hybrid technology, dynamic and balanced armature drivers Dynamic driver technology is implemented into a variety of products including loudspeakers, headphones and in-ear monitors Balanced armature drivers are primarily used in hearing aids, but they also see extensive use in modern in-ear monitors Package include: Xiao MI hybrid earphone and three sleeves (size: XS / S / l)