Product review (4 stars): These fit GE dryers made by LG - save $$
What you may not know is that LG made quite a few clothes dryers for GE.
GE is notorious for 'gouging' for parts.  They change the part number of this wheel and charge from $31 ~ $38 each roller, often without the shaft included.
I did some research and found that these wheels/rollers (whether genuine oem, 'approved oem', or just plain generic (I think all from Korea) will fit the following dryer model #ers:
DPGT650EH0MG,DPGT650EH0WW,DPGT650GH0MG,DPGT650GH0WW,DPGT750EC0PL,DPGT750EC0WW,DPGT750EC1PL,DPGT750EC1WW,DPGT750EC2PL,DPGT750EC2WW,DPGT750GC0PL,DPGT750GC0WW,DPGT750GC1PL,DPGT750GC1WW,DPGT750GC2PL,DPGT750GC2WW,PTDN800EM0WW,PTDN800GM0WW,PTDN805EM0MS,PTDN805GM0MS,PTDN850GM0WW,PTDS850EM0WW,PTDS850GM0WW,PTDS855EM0MS.

They've also been updated by this number that has a decidedly more narrow rubber edge:
LG Dryer Roller Assembly DE2002A  - REPLACES 4581EL2002C 4581EL2002A 4581EL2002B

Four stars for now until some time is put on them.  You don't have to always buy 4 but however many you are replacing you should get a new shaft included (these come with the new shaft - you reuse the old nut and washers).

There seems to be a very, very light oil on the shaft.  People refer to these erroneously as having bearings (lol) it's just a shaft and a 'bushing' spins on it.  I don't believe you should add lubricant to them, just install as they are. (unsticking an old frozen shaft & bushing with some spray teflon dry film is a different story though)