This is the THERMO SWITCH ASSY  that came from a Yamaha 64X 760 Waveblaster 2 wave runner. 

KNOWN TO FIT:

1996 Yamaha PWC Wave Blaster 760

1996 Yamaha PWC Wave Raider 760

1997 Yamaha PWC Wave Blaster 760

1997 Yamaha PWC Wave Runner 760

1997 Yamaha PWC Wave Venture 760

1998 Yamaha PWC Wave Runner 760 W

1998 Yamaha PWC XL 760 W

1999 Yamaha PWC GP 760 X

1999 Yamaha PWC XL 760 X

2000 Yamaha PWC GP 760

Should fit all Yamaha 2 stroke models but may require changing electrical connectors