This is an OEM product from Aqua Exclusive™ which is designed for use in the Green Line Bio Filter. This sight glass ensures that you can look directly into the filter, it is an inspection tool. This gives you optimal control over the operation of your filter. The seal is made of durable rubber, the bolts from SS316 and the sight glass of PMMA, which is 25 times stronger than glass. Note, do not use a cordless screwdriver, but loosen and tighten screws by hand with an hex key.
If you have any questions about replacing a bio filter part, please contact our support team. They are 24/7 available to help you.