i have stevens/savage sxs and lefever nitro sxs. i read a good description of a nonselective single trigger for a nitro special on this page -- there were no pictures or drawings. the description of the ithaca lefever nitro single trigger describing the single triggers system fully explain thw workings on the savage fox model B except for the inertia block on the fox. the fox single trigger will trip the hammers in sequence when dry firing. what is the purpose of the inertia block on the fox and why did the savage people use the inertia block and the ithaca/lefever guns do not have the inertia block. both trigger systems seem to work -- please explain the inertia block purpose on the fox model B ect