4 Fedi Periodontal Chisel, #6 Handle 4 Fedi Periodontal Chisel, #6 Handle CPF46 The 4 Fedi Chisel is used for incisions that remove or recontour soft tissue and to excise interproximal tissue with 3.3mm working end at 50 degree angle. Where to Buy x Category Dealer PartnersSales RepresentativeStrategic MarketsSchools RepresentativeAccutron™ Equipment Sales Zip Code Find RepresentativeReset Select a category, input a zip code and click on Find Representative, or explore the complete list here.