That would be our ST-485. A very good brushcutter, just nearly impossible to get parts for since Homelite has changed hands several times.
That particular carburetor has been discontinue for a number years but here they are suggesting using Walbro WT-458-1 to replace the Homelite PNs A03002 and A03003
As which Walbro you avtually in front of you the carburetor will be marked; hopeful engraved and not laser etched.