It's a good idea to keep your crampon toes and heels connected. Otherwise one or both might fall down the mountain. Replacement linking bars for CAMP crampons are found here. Sold in pairs with left and right bars included.
XLC Aluminum - Replacement bars for XLC 390, XLC 470, XLC 490 and XLC Nanotech crampons. These are made of aluminum for lightweight strength. 17.5cm long with 15 holes for your adjusting pleasure.
Skimo Dyneema Linking Strap - For Skimo race crampons. Made of Dyneems Webbing.