(Photo: Courtesy of Princeton Ski Shops)

Hot Chillys Thermal Wear, $24.95

What Double-layer long black underwear made of knitted jersey polyester that absorbs perspiration and traps warm air.

Units Sold 427 last month; 143 last week.

Why “We sell this primarily to people who do snow sports,” says merchandise manager Rick Carp, “but also to people who can’t bear the cold. My mom’s in her seventies, and in the winter she’ll wear these under her clothes just to run errands. Some people wear them as pajamas.

Princeton Ski Shops
21 E. 22nd St., nr. Broadway; 212-228-4400

Related:

• Archive: “The Best Seller”
• Articles by Denise Penny
• Table of Contents: Dec 20, 2004 issue of New York | Subscribe!