Merida Replaceable Derailleur HangerReplaceable derailleur hangers or dropouts are a breakable bridge between the bicycle frame and rear derailleur, protecting the frame from damage if gear components are impacted.Dropouts should be inspected before every ride and replaced immediately if damaged or bent to prevent potential failure and subsequent frame damage.Dropout hangers are specific to the bike and model year, if you are unsure of which replacement hanger you require please emailus with a picture of the old hanger along with the year and model of the bike.