The IODA Technical Committee have released a measurement interpretation to confirm that low-friction rings are not a "block" as referenced in the Class Rules and are therefore prohibited for use any on an Optimist Dinghy.

As a One-Design class the Optimist Class Rules are "closed rules" meaning that anything not explicitly permitted for use in the class rules is prohibited.

A rule change to permit the use of low-friction rings in place of a black has been drafted by the Technical Committee to be voted on at the IODA AGM later this year which if approved is expected to take effect in the 2026 version of the Class Rules when published.