Improve learning concentration; Quick send emotions, improve inso mnia, promote positive energy. Has a smooth will make a beautiful sound when which helps to relax the body and release stress. Fine production & High accuracy , this ergonomic handle is easy to hold. Used for medical Hearing detection,basic education classroom,science projects or stress relieving, instrument tuning, stainless steel, anti-rust, & long for time service., Manufacturer: Sxett