This lightweight trombone case is built to accommodate an F-attachment internally, and do so with sufficient protection to inspire confidence that the horn is not in any kind of jeopardy under normal expected cicumstances. It won't necessarily protect it from an overworked baggage handler in an airline travel situation, but for normal transportation to gigs and rehearsal, have no fear that the Gator GL-TROMBONE-F gig bag will get your main squezze there and back with no dings or dents.