Single Male to Double Male Splitter Piggyback Spade Terminal used when replacing an old style 2299001552 Schumacher Heatsink Rectifier Assembly with the new style 2299001587 Schumacher Heatsink Rectifier Assembly. Older units may have had an extra male spade for the fan speed controller to connect and these will be needed to facilitate the same after replacement with the new style recterfier.