THESE ARE FURNACE BLOWER ASSEMBLIES, REMOVED FROM CENTRAL HEAT AIR HANDLERS 230-240 VOLT UNITS SQUIRRELL CAGE, MOTOR, AND HOUSING ASSEMBLY VERY POPULAR FOR USE AS SHOP FANS AND VENTILATORS 230 VOLT FOR EASY PLUG-IN WIRING I HAVE SEVERAL, YOURS WILL VARY FROM PICTURE MOST ARE 3 TO 5 TON (AC) SIZE NEED A SCECIFIC SIZE TO REPLACE YOUR EXISTING FURNACE ASSEMBLY? CONTACT ME WITH OPENING DIMENSIONS, AND I'LL MATCH AS CLOSE AS POSSIBLE. RUN TESTED AND WORKING GOOD REPLACEMENT BLOWERS FOR THOSE LOOKING FOR A BLOWER TO REPLACE YOUR EXISTING HEATERS TECH TIP; MATCH THE WIDTH, MATCH THE BLOWER TYPICALLY, ALL BLOWERS HAVE THE SAME DIMENSIONS, EXCEPT AS THE BLOWER GETS BIGGER, IT GETS WIDER MOST ALL BLOWERS HAVE AN AIR OPENING THAT IS 11 1/2 TO 12 INCHES LONG. BUT THE AIR OPENING WIDTH, WHICH IS THE SAME AS THE BLOWER HOUSING WIDTH, IS ABOUT 8 INCHES IN A 2 TON, 50,000 BTU FURNACE BLOWER, GOES TO 13 to 15 INCHES IN A 125,000 BTU, 5 TON BLOWER. THE RADIAL DIMENSIONS GET A BIT LARGER AS THE BLOWER GETS LARGER, TOO PLEASE PROVIDE THE OLD BLOWER WIDTH, SO IT CAN BE MATCHED AS CLOSE AS POSSIBLE. BLOWERS WITH MATCHING WIDTH HAVE MATCHING CFM CAPACITY, SO A SIMILAR WIDTH BLOWER WILL WORK. THE REPLACEMENT BLOWER MAY NOT BE EXACT, SO SPECIAL MOUNTING MAY HAVE TO ADDED TO SECURE THE BLOWER