Mast sleeve only (as supplied with Blackgold masts). This mast sleeve is fitted around the Optimist mast at deck level and protects the mast from wearing, when used in conjuction with the Deck Collar.
As the mast rotates within the mast step, it creates friction which can lead to degradation of the mast tube or the hull. This can be prevented by fitting the Deck Collar to the mast step, and this mast sleeve to the mast at the same level. Instead of the mast rubbing against the boat, the mast sleeve will now rub solely against the Deck Collar. These items are fully legal under Optimist class rules.
Instructions for installation can be found here.