Commonly referred to as overalls or 'onesies,' the boiler suit was actually put into heavy rotation by none other than Sir Winston Churchill himself. Legend has it that he walked into his saville row tailor asking that they make him something he can jump in and out of in emergency situations. He also wanted to look 'smart' navigating the rubbled streets of war torn London, protected from mud and rain. Thus was born the onesie as a suit alternative. Personally, I think the good old navy blue ones from Army Navy Surplus are best, as they are always available in military colors favored by pilots. This one from Australian luxury denim brand One Teaspoon is also pretty cool because of its relaxed cut. Notice the drop crotch and inseam length to peg and roll them for a great look.