This is the replacement bushing for the 21 Speedmaster 3/16" strut or Speedmaster Sport 20 Struts. Fits: Part# ros-spdss-001 Part# ros-spdss-002 Part# ros-spds-005 Part# ros-spds-017-SK Specs: Inner dimension: 3/16" (.187", 4.75mm) Outer dimension (the part that rides in the stuffing tube): 7/32" (.219", 5.56MM approx) NOTE: Fits into K&S # 131 1/4" brass stuffing tube. This will not fit the Speedmaster Stinger Style strut.
