Eyeglass frame sales usually come with an asterisk. Those $39* frame sales often have fine print that's difficult to read because, well, we need stronger lenses.

What it usually says is that the $39 frame price is only good when a complete pair of glasses is purchased, including lenses. That's when the savings on the $39 frame is often eaten up by above market prices on lenses.

One way to avoid being overcharged is to check lens prices at Costco Optical after you get a quote from your own optical shop. Even non-members can call Costco to ask for a price. Tell the attendant what you want--for example, high-index, progressive no-line bifocal with edge polish. Costco's prices are frequently significantly lower. Lenses that cost $400 at an optical shop may be half as much at Costco, according to Consumer Reports.

The sale happening from 10 a.m. to 6 p.m. Saturday and 11 a.m. to 5 p.m. Sunday at Southdale is also a $39 frame sale. The difference is that frame buyers don't have to purcahse a complete pair of glasses. They can choose to buy lenses elsewhere for an extra $10 (as noted in, you guessed it, the asterisk).

What's different about the sale put on by Southdale Optical and Inver Grove Heights Family Eye Clinic is that lens prices are quoted too: $57 for single vision and $119 for a progressive no-line bifocal. Other lens prices may be higher, such as an extra amount for stronger prescriptions. Confirm the lens price before buying.

About 16,000 frames will be on display. The frames are purchased for pennies on the dollar from optical shops going out of business around the country, said Chris Gregg, an optician and owner of IGH Family Eye Clinic.

Gregg has been a proponent of truth in advertising in the eyeglass industry since the late 1990s. He complained to the Better Business Bureau about an optical shop that said its light weight lenses were an exclusive to its shop. It wasn't true and thanks to Gregg and the BBB, the company changed its advertising.

The sale is located on the second level of Southdale below Dave & Busters.