MSMA (monosodium methanearsonate) is an arsenic-based grass killer. It kills grassy weeds such as crabgrass and goosegrass without harming most turfgrasses. It contains organic arsenic that, according to the University of Tennessee Extension, is less harmful than aspirin.
There are several styles of hearing aids available, from the smallest - Invisible in the Canal (IIC) to the largest and strongest - Power Behind the Ear (BTE), and the very popular Receiver in the Canal (RIC) - made to fit most hearing losses while remaining nearly unseen.
A hearing aid or deaf aid is an electroacoustic device which is designed to amplify sound for the wearer, usually with the aim of making speech more intelligible, and to correct impaired hearing as measured by audiometry.