This is a 1 hp gain on top and a 3hp gain down the powers ovverev. This is a replacement end cap for the 2020-21 KTM XCW and XC - TPI Bike and Husky TE and TX - TPI bike. It has a spark arrestor in place, weighs the same as the stock end cap and makes more mid to top power than an aftermarket muffler. It makes more since the intenal core is longer. It’s also quiter than an aftermarket muffler, since it has twice as much packing. You can easily remove and clean the spark arrestor screen as needed, but it’s not needed much on the TPI bikes. You’ll drill out the stock rivets to remove the stock one and then this just bolts in place.