@interface _DKBluetoothMetadataKey : NSObject + (id)address; + (id)batteryLevelHeadphoneLeft; + (id)productID; + (id)batteryLevelHeadphoneCase; + (id)isUserWearing; + (id)isAppleAudioDevice; + (id)batteryLevelHeadphoneRight; + (id)name; + (id)deviceType; @end