OK, Checking with Dwyer Mast, The model #DM450 extrusion is used on both O'Day 22-2, 38 lbs.; and 23-2; 40 lbs. with the exception that the 23-2 is 6" longer. These weights do not include the required hardware. Having owned an O'Day Mariner for 35 years, I assure you that the mast sizes between the O'Day Mariner and the 22-2 are greatly different. It was interesting because the Mariner mainsail fit very nicely on the 22-2. Having bought sails for both boats, the North cruising sails for the 22-2 are most beautiful and bullet proof; even though they were made in Sri Lanka. Maybe that was an advantage. They are meticulously crafted with bells and whistles.