The official Briggs news release says:
Rule Update: Clutch Clarification
For 2020, all participants must compete with an approved clutch model from one of three long-time supporting and proven manufacturers - Max-Torque, Hilliard and Noram. This will simplify the decision process, provide a consistent price point, and help tech officials efficiently do their job. The eight approved clutch models can be found at numerous dealers throughout the U.S.
The Official 2020 ruleset states:
32.b. Sportsman, Junior 1, Junior 2, Senior, and Masters Classes must run one of the following clutches:
1. Inferno Racing by Hilliard: Fire, Flame, Blaze or Fury
2. Max-Torque: Draggin Skin or SS
3. Noram/Premier: Magnum, GE, Ultimate or Stinger*
* NOTE: Noram/Premier Stinger must be converted to stamped drum (Noram P/N 01600715) by May 5, 2020 to be legal for competition.
That's 10 clutches listed in the ruleset verses 8 in news release. My guess is the news release was put together before the ruleset was finalized but after all the controversy over the clutch rules, you think they would get something as simple as this correct.