The Horwood Bagshaw Clover Harvester, also known as the HB, is the most common machine for harvesting subterranean clover and annual medic seeds in Australia. In order to improve seed harvest performance and reliability, a number of modifications to the HB have been developed and trialled. While some modifications are common, many are confined to particular seed producing regions and are unknown to other seed producers. This factsheet highlights some of the most effective HB modifications across regions.