The QXE01 chain hook is installed in the tension pulley and keeps the chain tight while folding/unfolding and while carrying the bike, preventing any chain drops without increasing the folding/unfolding time. No more frame scratches from chain hits.
The QXE02 version keeps the same functionality as the QXE01 model, keeping the chain tight while folding/unfolding and while carrying the bike, but also adds an extra function as a chain tensioner to help preventing chain drops and chain stay hits while riding your Birdy.
| P/N | Function | Compatibility | Body material | Weight | Colors* |
| QXE01 | Chain hook | Folding bikes with rear derailleur (it attaches to the tension pulley bolt) | CNC alloy | 20 g | black, red, gold, silver |
| QXE02 | Chain hook and tensioner | Folding bikes with rear derailleur (it attaches to the tension pulley bolt) | CNC alloy | 26 g | black, red, gold, silver |
*More colors are available as a customization option.