579897MA simplicity briggs and stratton hex shaft. THIS IS A USED OEM PART. If you have any questions about this item, please feel free to sent a message, I will do my best to assist. Please confirm this is the correct part for your equipment, by using a oem parts diagram. If you need assistance let me know I will do my best to help. I would need the full model and serial number, and also the spec, code or type number for engines. I try to respond to all messages, if I miss your message please sent a follow up message.