The only two Marconi mainsail systems that I have not yet found a way to safely secure the Mast Mate are the internal mast roller furled main and the new Bat car track system. In both cases I have recommended to the owners that they install an additional track slightly off-center for not only the use of the Mast Mate, but also for an emergency back-up main and/or storm sail. The mast mate is not safe to use on trackless masts or on masts that have an extreme rake. Recently I have designed a good way (yet untried by me) to attach the Mast Mate to the mast slot in an internal roller furling main system. (see diagram)