JBL MTC-CSTETH1 Ceiling Speaker Grille Safety Tether (10-Packs)JBLs MTC CS Teth1 is a kit of 10 retrofit safety tethers that work with JBL press in grille type ceiling loudspeakers (Control 10 Series, 20 Series, 40 Series, and 226). If a grille were to work its way loose, the tether is intended to catch it and keep it from falling to the ground where it could otherwise cause damage or harm. The tether consists of a short length of flammability rated aramid tether cord and an adhesive tab. The thread end attaches