Rewiring a 4 pin Nidec BetaV TA350DC 12DCV fan to 2 wire conection

[SemperFi5985]

I am helping my local school replace a fan unit in their "Mascot" head gear that burned up. I ordered what I thought was the correct replacement but instead of the 3 wire ((Nidec BetaV, TA350DC, 12V) red, yellow & black, of which only the red and black wire were used through an on/off switch to turn the unit on) I got a 4 wire fan ((Nidec BetaZ, TA350DC, 12V) red, black, blue & yellow) unit. I am not sure how to wire this through a on/off switch. Can anyone help we with ideas here.

Thanks
Chris H

 

[HillBillyAsian]

the red and black wire just the same, the other 2 wires are for rpm control and pwm.