A CNNMoney analysis of Census data shows these jobs -- which have roughly the same amount of men and women workers -- have little disparity in salaries.
As a heavily unionized, quasi-government agency, it's no surprise that the United States Postal Service has a big focus on equal employment opportunities for both men and women.
"There is far more transparency about wages in the public sector and are there are not penalties for discussing salary," said Fatima Goss Graves, vice president of education and employment for the National Women's Law Center.
Full-time women postal clerks made about $52,601 in 2011, 98 cents to the dollar of their male coworkers. That's according to a CNNMoney analysis of Census data.
A pay gap that small is likely explained by some men working slightly longer hours.
But postal workers don't exactly enjoy job security these days.
USPS has reduced its ranks by about 300,000 workers since 1999, and plans to cut more jobs under its proposal to eliminate first-class mail delivery on Saturdays.