A rigging toggle adds length to a shroud or stay without compromising its integrity. Many large boats, due to long rigging lengths and the associated stretch in new wire will have one or more rigging toggles that essential provide additional adjustment. As new rigging stretches and the turnbuckle runs out of adjustment, a rigging toggle is removed providing more adjustment again.
This toggle adds 1-1/2" of length from pin to pin and is used on Catalina 27 and Catalina 270 to connect the forestay to the masthead for boats with headsail furling. If your turnbuckle does not allow for this much adjustment, consider buying a new forestay.
This toggle can also be used on the Catalina 28 and Catalina 30s at the deck to provide some extra length to the shrouds for any reason.