Because it’s a new take-out fan motor from Welling Service Co., made for air conditioner-humidifiers. Rated for 115VAC, 16W, spins approx 1400 rpm via a 2-1/2” x 5/16” threaded shaft which will most likely have a nut on the end. Has 12” long leads, (2) of which are for a 6uF capacitor (not included). Rotates counter-clockwise and measures 2-5/8" dia x 2-7/16" deep. Has (4) mounting holes on wings. Welling part #YSLB-16-002-001.

This approx 15” long squirrel cage blower assembly operates at 115VAC, draws 20 watts and rotates at a gutsy 1500 rpm. Requires a 3uF start capacitor (not included). Squirrel cage is 10-5/8" long x 4-3/8" with a 3-5/8” x 4-3/8” motor. Has a 1/4" x 1" shaft, and rotates counterclockwise. UL.

This takeout fan from an un-used AC unit draws 42W at 115VAC and spins both a 12” dia, 5-blade fan blade and a 7-1/2” x 2-3/8” squirrel cage at approx 900 rpm. The motor in the middle measures 3-3/4” dia x 3-1/2” with a 5/16” shaft that extends 2-1/2” out of one side and 2-1/8” out of the other. Has 14” leads and rotates clockwise. You’ll need a 250V 6uF start capacitor. UL.