Fred Perry Loop Back Navy Blue Sweat Pants. Elevate your casual style with the Fred Perry Loop Back Navy Blue Sweat Pants. Made with a comfortable loop back fabric, these pants feature a classic navy color that pairs well with any outfit. Enjoy a cozy and stylish look while showing off your love for Fred Perry.. 1 Back Pocket, Cuffed Bottoms, Navy Sweatpants. Drawstring Waistband, Loopback Sweatpants, Slim Fit. Stripe Design On Back Left Pocket, Brand Logo On Front Left Pocket, 79% Cotton, 21% Polyester. Style Code: T2515 608