Original Yamaha part. Part number: 23x-22199-00. Should fit following models (please check your manual):
1983 Yamaha YZ250K
1983 Yamaha YZ250K
1984 Yamaha YZ250L
1985 Yamaha YZ 250
1983 Yamaha YZ490K
1984 Yamaha YZ 490
1985 Yamaha YZ 490
1984 Yamaha IT 490
1986 Yamaha TT 350
1987 Yamaha TT 350
1983 Yamaha TT 600
1984 Yamaha TT 600
1985 Yamaha TT 600
1986 Yamaha TT 600