1. This air filter is designed for GY6 scooters and all - terrain vehicles (ATVs) and belongs to the category of air filters. It has a reasonable design and multiple matching specifications, which can meet the needs of different users. 2. In terms of connection, there are various options for connection threads, seal ring sizes, inner diameters, intake pipe diameters, and exhaust pipe diameters, including 35 mm, 38 mm, 42 mm, 45 mm, and 48 mm. These options can ensure a closer and more precise fit with various vehicle models. 3. It comes in two types: straight - mouth and slant - mouth, which can adapt to different installation environments and usage scenarios. The flexible design makes installation more convenient. 4. Regarding its external dimensions, the diameter is 45 mm, the width is 100 mm, and the height is 120 mm. The overall outer diameter × height is 12 × 10 cm. This size design can ensure the efficient filtration of the air filter without taking up too much space. 5. As a motorcycle modification accessory, it features high flow, which can provide sufficient clean air for the engine, helping to improve the performance and efficiency of the engine. It can make the vehicle's power output more stable, bringing a better riding experience. Whether for daily riding or driving on special terrains such as beaches, it can perform well. It is a good choice for improving the performance of GY6 scooters and all - terrain vehicles.