Signia 312 size battery which is mainly suitable for use in behind-the-ear (BTE) and full-shell (ITE) hearing aids. Signia hearing aid batteries are high quality, and powerful with long life. This Signia battery provides a long running time at a constant voltage level thus contributing to optimal hearing aid performance. These batteries are reliable and safe to triple-sealed high-quality components. These batteries are environmentally friendly as they are 100% mercury free.