I'm confused about whether the pure lead series of Powerbelt bullets is legal in muzzleloader-only big game hunts. Can you clarify this?

The current Idaho equipment rules for muzzleloader-only big game hunts require that the weapon be "loaded only with a patched round ball or conical non-jacketed projectile comprised wholly of lead or lead alloy. Sabots are not allowed." The Idaho Fish and Game Commission and Fish and Game staff have confirmed the plastic gas check on the pure lead series Powerbelt bullet does not meet the definition of sabot - defined as "a sleeve placed around a projectile so that it can be fired from a weapon with a larger bore." The bullet specifications meet the minimum diameter, lead or lead alloy, and non-jacketed requirements.