Most boats have the "Racing Boom"
See this link on the Rig-Rite website
J/30 Boom Assemblies are complete but do not include Gooseneck Toggle, K-10345A, or standard Vang Bracket, K-1757-1, due to the increasing use of Solid Vangs (which require special brackets). Standard Boom Assemblies use the Flush-cut Outhaul Assembly, K-11471, while Racing Boom Assemblies use the lightweight Cut-away Outhaul Assembly, K-43008, with special tapered end cut to further reduce weight. Both styles are fully class legal.