1. Product specifications: Suitable for 700X35 - 38 - 40 - 42 - 43c bicycle tire inner tubes. 2. More durable: This bicycle inner tube is made of high - quality rubber. It has advantages such as better sealing performance, ozone resistance, aging resistance, shock absorption, and electrical insulation. 3. Product information: Weight: 170 grams per tube; Long American valve stem: SV48MM/A/V48L. 4. Practical accessories: Suitable for most bicycle wheels. The rim tape is more robust and has a better anti - puncture effect. 5. Safe bicycle tire: This rubber inner tube can play a shock - absorbing role on bumpy roads, making cycling more comfortable and safe. It is heat - resistant and wear - resistant for daily use. 6. Material: Rubber. 7. Color: Black. 8. Package contents: 2 bicycle inner tubes. 9. Only the above - mentioned package contents are included, and no other products are included. 10. Precautions: Due to light and different monitors, the color of the items in the picture may vary slightly from the actual product. The allowable measurement error is ±1 - 3 cm.