The TBM kit is an upgrade kit that allows owners of SPRs with the standard DBM magazine assembly (.308 only) to upgrade to the TBM magazine assembly with 5 and 10-round magazines (DBM is only 4-round capacity). Kit replaces the trigger guard assembly. Does not require modification of or fitting to the rifle. Does not fit SPRs with hinged floorplate. TSRs or PBRs with DBM equipment might require fitting by a gunsmith. Retrofit on SPRs can be accomplished in minutes and requires few tools (torque wrench is required). Comes with new trigger guard/bottom metal, 5 and 10-round TBM magazines, new action screws and instructions.
Big Book Catalog, Issue:69, Page:179
Fits FNH SPR rifles (will not fit SPRs with hinged floorplate). Includes Trigger Guard/Bottom Metal, one 5rd and one 10rd magazine.