down to the lemon-yellow thread under the flap pocket

These are designed with slim arms

but it's been given a rinse to make it comfortable off the shelf

but not your 501 wide style

The Flat Head 3009 Slim Straight - 14.5oz Selvedge Denim (Unsanforized) belts down to the lemon-yellow threadThe Flat Head Pioneer 3XXX jeans are a 14. 5oz denim woven on old shuttle looms. This denim is full of character and famous for its fast, high contrast, vertical fading. Even the pockets are designed to age uniquely, as they are specially double stitched first with a poly cotton thread for strength, then with a cotton thread that will shrink, leading to puckering that helps with the fading. This denim is unsanforized and will shrink up to 1. 5" in the