For BG86 blower, there is a plastic protrusion that seats into the air-filter housing. Compatible High Quality Aftermarket Carburetor Fits For Stihl SH56 SH56C SH86 SH86C BG86 Blower Replace Zama C1M-S261B Carburetor Replace Part number: 4241 120 0616 Please Note: This is High Quality Aftermarket Parts And Tested For Maximum Performance. colour: Material:metal Package Contents: 1 * Carburetor 2 * Gaskets 2 * Primer Bulb 1 * Fuel Filter 1 * Fuel Line 1 * Spark Plug Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.