R.E. Thomas Marine heavy duty cast bronze stuffing boxes. SB series. Made with precision machined threads. Engineered to meet the rigorous demands of both commercial and recreational mariners who prefer a traditional shaft sealing system. Reinforced mounting flange can be cut to size to fit a variety of applications, including Downeast style lobster boats with narrow keels. Suitable for lower horsepower boats. Offers exceptional quality, safety, performance and value. Made in Downeast Maine.