Shortly after the launch of The Standard this one, The Original, followed and for some time customers had a choice between the Utilikilt "skirt" and the kilt. Looking upon the kilts from behind there is hardly any difference, but the front of The Original has an apron like a traditional kilt, just not as wide. The buttons have a function. They connect the outer and inner aprons and keep the kilt together rather than straps and buckles on a traditional kilt.
Judged from the many pictures appearing on the internet the black version might be the most popular Utilikilt Original. It can be worn at jeans waist level or higher, like you would normally wear a traditional kilt.
The length? No rules. Traditional kilt length, a little bit longer - you often see Utilikilts covering the wearer's knees - or a little bit shorter. It's your choice. My utility kilts will, when worn low, almost reach down to the top of my knees. But I'll often wear them higher.
A few years ago Utilikilts redesigned their kilts. And the "Original" was replaced by the "Spartan".