10pcs 46mm x 1.5mm Piston Ring Fit 028 029 MS280 MS290 BR400 380 320 SR420 251 350 446 746 950 150 151 156 Piston ring set designed to fit various 2 stroke engine chainsaw and models.Matches specifications for use in models including 028 029 MS280 MS290 BR400 380 320 SR420, Super XL, 251/S 950/S/FS 951 956 350AF SUPER 746 S 746 T 446 BP 446 BP Ergo, 150 151 156 and other similar units.Each order includes 10 pieces of piston rings.Designed for straightforward installation and.Inspected before packaging to dimensional accuracy. Compatibility Disclaimer: This is an aftermarket replacement part.Any brand names or model designations mentioned are used solely for the purpose of demonstrating compatibility.