Get a new - or replace your damaged - spark arrestor with this United States Forest Service approved Pro Circuit Spark Arrestor screen. U.S.F.S.-approved spark arrestor screen. Sold individually. Detailed Specifications: This Pro Circuit Spark Arrestor is United States Forest Service approved (USFS), and will fit 3.5" or 4" four-stroke silencer cans. This is a 1-3/4" spark arrestor screen for big bike 4" cans 2007 and up. Pro Circuit P/N: PC4000-0001.