Please read the full Instructions for Use provided with the product prior to using. •Check your size on the sizing guide on the back of the packaging: 1) Lightly place your little finger alongside the first white line, over the graphic. Do not press your finger down 2) Find the corresponding line your little finger fits within. If in-between sizes, select the larger size Alternatively follow the online sizing guide options •With your opposite hand, reach over your head and pull your ear upwards •Hold the earplug from its end. Applying pressure with your thumb, insert the earplug using a gentle rocking motion •Do not push any further than the third flange •If after insertion there isn't a significant reduction in noise or the earplug is loose, the earplug may be incorrectly inserted or sized too small. Check insertion or please purchase the larger size •Conversely should it not insert at all beyond the first flange the earplug is too big for the user's ear. Please purchase the smaller size •Effectiveness check: Cup hands over the ears then move hands outwards. Should a noticeable change in sound occur, check earplugs are properly inserted