TSA Precheck Bag for Liquids
 

Hello - For those with Precheck (via Precheck or Global Entry), I'm wondering what type of one quart-size bag you use for your liquids for carry-on luggage. Does it have to be clear? Can it be any toiletry bag that is quart size?

Thanks for your help.

The TSA doesn't specify clear or not bag.

What is the 3-1-1 liquids rule?

Per the citation by Boggie Dog it doesn't have to be a clear ziplock bag. Even though that's what's illustrated.
Per dozen of anecdotes, anything outside of a TSO's expectation is likely to confuse them and cause some level of delay.
However, in the TSAPre line, since it doesn't have to be separated, I don't think a standard toiletry bag would even be noticed.

Boggie Dog and rickg523 are both correct; but since you asked specifically about PreCheck, it's also worth explicitly stating that the rule doesn't change depending on whether or not you have PreCheck.

Also, some non-US air travel security authorities do require that it be a clear bag; CATSA in Canada is an example that comes to mind.