I just checked the Aerus website, which lists three different nozzle belts (I've added some clarification):
#0493 - PN-1 through PN-4
#48359 - PN5-2003 (non-JEI motors--often listed as replacements for PN5, PN6, & PN7, but including other models made until 2003)
#49431 - JEI motors (2004-present)
Canister Power Nozzle Models: N137Z, N115Z, N137Y, N137X, N115Y
Commercial Upright Models & ProTeam: U129Q, U129S, U129U
Lux Guardian Upright Models: U147G, U147H
Aftermarket part #s I've seen are:
26-3300-08 (PN-1)
26-3310-04 (PN-2 - PN-4)
26-3315-02 (PN5, PN6, PN7, & others including Veridian U139K)
26-3320-02 (Canister model suffixes X, Y, Z; Commercial Upright model suffixes Q, S, U; Household Upright model suffixes G, H)
So, it could also be that you bought a 26-3320-02.