Jet kits come with all the hardware you need to convert your motor to a jet.  (You will need to use the water pump off of your existing lower unit.)

Notes about this kit:

Add $160 for 6 1/8 stainless steel impeller upgrade #1737.

Med Jet Kit

For use on – 40HP, 45HP, 50HP Yamaha 2 Stroke Motors

Price: $