This post is part of Mashable’s Spark of Genius series, which highlights a unique feature of startups. If you would like to have your startup considered for inclusion, please see the details here. The series is made possible by Microsoft BizSpark.

Name: Blank Label

Quick Pitch: Blank Label is a provider of co-created dress shirts, customized by users with an online dress shirt design application.

Genius Idea: If you’ve ever been frustrated by the lack of dress shirt options at JCrew or Brooks Brothers, Blank Label may just be the solution to your woes. The company’s online shirt design application enables consumers to co-design their own dress shirts with a wide range of customizable options, from fabrics and lining colors to fit and stitching details. What’s more, you can get a great custom shirt for only $45, and the company offers full refunds on all of its individually made products.

The only downside? You’ll have to wait three to four weeks to receive your order.

The step-by-step design app is very easy to use, which is impressive given the extensive array of customizable features. Although I know next to nothing about men’s dress shirts, I decided to give the app a whirl.

First, I was presented with 40 different fabric options, from “Rich Poplin Cream White” to “Modern Man’s Lavender,” followed by four different types of collars: normal, narrow, wide and button-down. I could upgrade to a “complete contrast” collar for an additional $9 or a special inner lining for an additional $6. I opted for a shirt in “Connecticut Oxford Orange” with a button-down complete contrast collar in white.

Next, I chose between three different types of cuffs: single button, double button and French, with the option to select a custom fabric for the sleeve or cuff lining for $12, a complete contrast cuff for $9 or a custom lining in the inner cuff for $6. I decided to pay extra for outer and inner cuffs in white to match the complete contrast collar I had selected earlier.

After the cuffs, I customized the style of my shirt’s placket, which is the strip of fabric on the front of the shirt that the buttons are stitched onto. I chose a standard placket (stitching on both sides of the button row) rather than a French (stitching on one side) or covered placket.

Since my shirt already had a lot of trim, I decided not to add a complete contrast, military/epaulet or double strip shoulder to my shirt. I also kept it simple by adding only one pocket, rather than double pockets in contrasting fabrics for an additional $9.

In the last stages, I opted for lavender buttons and decided against monogrammed initials or a custom label.

On the last page, I was presented with a remarkable range of fit options. I could select sizes (S-XXL) according to collar circumference, sleeve and shirt length, and chest and midsection measurements. I could also opt for a classic or slim fit, and choose between a tucked and untucked style. Lastly, the app asked for details about the wearer’s body type, height and weight and provided a box for additional requests. Clearly, Blank Label cares about fit.

Altogether, my shirt cost $73. I haven’t been able to inspect the quality of the fabric and workmanship in person, but it strikes me as a very reasonable price for a custom-styled and fitted shirt.

Have you or do you plan to use the app? What other features would you like to see? Share your ideas in the comments.

Sponsored by Microsoft BizSpark

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Tags: bizspark, blank label, fashion, web app