At this time of year, it's easy to imagine the sewers beneath Walnut Street awash with dry, flaky skin cells as the city's pampered class exfoliates in preparation for beach season.

Walnut Street is where the upper crust decrusts. For slough-it-yourselfers, there's the Vietnamese shopping plazas of Washington Avenue, where several wholesalers to the salon trade operate.

U.S. Maxim, at 1119 S. 11th St., is particularly welcoming to retail shoppers, who can buy anything from a gallon tub of exfoliating lotion - about $25 and roughly the size of the pump-mustard vats at Citizens Bank Park - to single bottles of salon-brand nail polish like OPI and the newly trendy Essie line ($3.50).

Owner Binh Tong says the hot salon colors for summer are Essie's Mademoiselle and Sugar Daddy, both featured in April's issue of In Style. (They're listed as #384 and #473, respectively, in the to-the-trade numbering system on his display racks.) U.S. Maxim's cute, cheap polka-dot flip flops ($1 a pair) are a pretty showcase for a fresh pedicure. *

U.S. Maxim, 1119 S. 22th St., 215-467-1328. Open Monday through Sunday from 9 a.m.-9 p.m. Closed Saturdays.