A. Product Introduction - **Product Name**: Trailer Connection Device - **Material**: Carbon steel - **Features**: Rust-resistant, durable, wear-resistant, high hardness - **Size Details**: - Trailer Connection Device: Length: 5.7 cm/2.24 inches, Height: 3 cm/1.18 inches (approx.) B. Advantages Compared with Traditional Stainless Steel Materials Our carbon steel bicycle connection device is more stable and firm than traditional stainless steel materials. It is less likely to deform, resistant to rust and corrosion, and has a relatively long service life. C. Installation Instructions 1. First, install the towing device on your bicycle. 2. Then, connect the bicycle trailer with the connecting pin. After that, the installation is completed. The installation of the bicycle towing device is relatively quick and easy. You can finish the installation in a few minutes. Our bicycle connection device has a good connection effect. It is less likely to disengage and will not loosen on its own, ensuring a high level of safety during cycling. D. Compatibility It is suitable for most bicycles, such as mountain bikes, folding bikes, ordinary bicycles, etc., and is also applicable to children's trailers, pet trailers, etc. E. Precautions - Due to differences in light and screen settings, the color of the product may vary slightly from the picture. - Due to different manual measurement methods, slight differences in size are allowed. F. Packaging Contents 1. Option A: - 1 x 90-degree trailer connection device - 1 x buckle 2. Option B: - 1 x 135-degree trailer connection device - 1 x buckle 3. Option C: - 1 x 135-degree trailer connection device - 1 x quick-release buckle 4. Option D: - 1 x trailer connection device - 2 x buckles