The numbers sound like entries in the "Guinness Book of World Records." Every day, more than 2,300 shoppers -- of whom 65 percent are retired military -- go through its door. There are 25 check-out lanes and 3 acres of total floor space (including the adjoining warehouse). The commissary at Ft. Belvoir, raking in $55.3 million in total sales for 1986, is the busiest in the world.

Not even Giant or Safeway can top it. Safeway has only two stores in the area that ring up more than $25 million annually. Giant has 25 stores that sell more than $25 million worth of groceries a year, but only one store even gets close to Ft. Belvoir's total -- its Baileys Crossroads location, which grosses $48.5 million annually, according to Food World, a publication that tracks the local supermarket industry.

Giant, Safeway and other area markets can't beat the prices, either. Compared with his local supermarket, according to retired Lt. Col. Edwin Siwik, the price savings at the commissary are "considerable." Siwik, browsing in the meat case at the Ft. Belvoir commissary on a recent afternoon, said he spent 30 years in the service. "This {the commissary} is one of my benefits. I'm gonna keep it," he said.

According to Bob Waterhouse, manager of the Ft. Belvoir commissary, his customers save approximately 28 percent on their grocery bills as compared with what they would spend at a conventional or warehouse-type supermarket in this area. Waterhouse said that the commissary, run strictly on a non-profit basis, sells goods for exactly what it pays for them. There is no sales tax, but a 5 percent surcharge is added to each sale to pay for operating costs. Funds appropriated by Congress are used to pay employe salaries and finance commissary inventory.

Ft. Belvoir's wholesale prices tell a lot about how much conventional supermarkets mark up their prices. In fact, the produce buyers at the Defense Subsistence Office (DSO) in Landover, the facility that buys produce for the commissary, say that they are often astonished at the mark-ups of produce in conventional supermarkets, which can hover near 100 percent.

Indeed, a few weeks ago, yellow squash were selling for 65 cents per pound at the commissary and $1.19 at Safeway, or 83 percent more. On another day, bananas were selling for 30 cents a pound at the commissary and 50 cents per pound at Safeway and Giant, or 67 percent more.

As for the quality of the goods, it depends on who and when you ask. Among the few shoppers questioned when Waterhouse was present, all had complimentary things to say about the operation. Without the presence of the store manager, an equal number of shoppers had complaints, primarily focusing on poor-quality produce, unavailability of certain brand names and basic items being frequently out-of-stock.

Aside from the price differences and shoppers dressed in fatigues and combat boots, there are a few other unique features at the commissary. Bread & Chocolate, the local bakery, operates an attractive concession, selling everything from brioche to fruit bavarians, and dog food is displayed in giant-sized dog houses situated before the entrances to the check-out lanes. Lastly, a department selling items in small portions is decorated with American flags and a banner reading: "Single Soldier Section ... Serving the Most Deserving."