Genuine Mazda Miata OEM Rain Rail Soft Top Rear 2006-2015
#8 in illustration
This is the "rain gutter" type piece that every Mazda MX-5 Miata already has. It is located behind the top (you can't see it until you remove the top) and funnels the water that runs down between the top and the body of the car to drainage holes. If this piece is cracked or brittle, serious water damage can occur in your Miata.