No need to weld the filter, the filter is docked with your car instrument plug and socket. Simple and efficient operation, safe and reliable. MILEAGE BLOCKER FOR A3/S3/RS3/8Y 2020-2023 There are some differences between the product and the picture due to different batches, which not affect normal use Notice:This Product is NOT for dash Mi-leage KM or stop Mi-leage, please notice before you buy. Not for stop milage running !!! The Compatibility Is Just For Please Compare The Part Number With Your One Before Purchasing! Note: Installation guide not included, we strongly recommend you professional installation. Please check as much as possible to make sure the item is what you need. Easy DIY installation:Plug-in face and ridges on the connector a smooth installation process. Easy to use with multiple key combinations. Leaves no trace when you remove it: no soldering or cutting of wires required. No error messages on the speedometer or navigation panel. Comes with premium-quality plugs and heat- cables. After detaching the module, the mileage doesn' increase spontaneously. For the mode that alters the mileage entirely, we allow a deviation of up to 1% of the driven distance. Provided details about stopped mileage are only approximations, and there might be such minor differences. Function: ACTIVATION & DEACTIVATION the OK button for 10 seconds. Repeat the process to switch from mode to mode. The speed display and the assistance systems operate smoothly in all modes. Colour:Black Material:plastic Package Contents: 1 x Special Filter Only the above package content, other products are not included. Note: Light reflection 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.