If you use a standard incandescent medium based bulb, no great than 60 watts, which is the fixtures limit, and you hard wire it to a wall switch equipped with a dimmer/rheostat, you can dim the fixtures.

It doesn't say if the high low switch is along the cord or on the fixture. If it's on the cord, you'll be cutting it off. If it's on the fixture, you can use that in place of the wall dimmer.

So neither needs to be dimmable if the bulb is incandescent. Who knew?! I sure didn't. Thank you so much for enlightening me (pun intended), beverly!

Many LEDs and some compact fluorescent (CFL) bulbs you can use can also be dimmed using a common dimmer, although dimmable CFLs aren't usually all that good.

I have a similar question about a chandelier - Specs do not include "dimmable" - uses 40 watt candelabra bulbs, 4.5 W LED candelabra or 9W CFL?

The fixture and the switch.