Hat sweat band mounted Behind The Ear (BTE) hearing aid option

With Over The Counter (OTC) hearing aids now becoming more available and companies becoming more price competitive, as an electrical engineer I'm experimenting with multiple pairs of hearing aids tailored to different life activities such as exercise, sports and occupational applications.
Currently I've mounted my new BTE hearing aids under my ball cap sweat band and run the clear plastic optical tube out to each ear. The hearing aids still function well although I have to remove the hat to adjust volume and environment settings. One advantage is that unless you lose your hat you can't lose your hearing aids!