FOR SALE BILLET ALUMINIUM DUAL PORT MUFFLER COVER. ADD THIS TO YOUR MUFFLER HOUSING FOR A CUSTOM TRIPLE PORT. The item "BILLET ALUMINUM DUAL PORT MUFFLER COVER FOR STIHL CHAINSAW 064 066 MS660" is in sale since Thursday, October 26, 2017. This item is in the category "Home & Garden\Yard, Garden & Outdoor Living\Outdoor Power Equipment\Chainsaw Parts & Accs".The seller is "customchainsawparts" and is located in Arlington, Washington. This item can be shipped worldwide.