Westclox Factory Mainspring for GTA-3 Travel Clocks P/N G22010

Westclox Factory Mainspring P/N G22010 (or 1-G22010) for Westclox GTA-3 Alarm Clock, new in envelope. Could also very well fit in other travel clocks. Mainspring appears to me to be a alloy mainspring but it isn't marked as such so I won't swear to it. I specialize in hard to find watch parts and all watch parts are unconditionally guaranteed. Images do a suitable job of representing the item.