With a name like "Bark Box®," Westcoast Saw lets you know exactly what you're getting! This muffler cover is constructed out of stainless steel and hand TIG welded. It also has a spark arrester built in. Made in the USA. Expect cooler running temperatures, a rowdy sound, and 6-10% horsepower gain. Installation Note: If your saw is M-tronic it will be tuned in by the third or fourth cut after installation. If your saw is non M-tronic, we recommend re-tuning after installation. Bark Boxes are compatible with 2-piece muffler covers only. Specs Spark arrestor screen size of 0.021 More horsepower and torque Improves power throughout RPM range Brings down engine temperatures Corrosion resistant Constructed of 304 stainless steel Hand tig welded Made 100% in the USA One-year warranty included Ⓓ CANADA DESIGN REG. NO. 210518, WESTCOAST SAW, LLC Stihl® is a registered trademark of Stihl® Incorporated and is used only to describe their products. Universal Power Port | Top Handle Mufflers | Clutch Cover For Select Stihl Saws