EMPLOYEE CONFIDENTIALITY, NON-COMPETITION, AND NON-SOLICITATION AGREEMENT

Exhibit 10.04

EMPLOYEE CONFIDENTIALITY, NON-COMPETITION, AND

NON-SOLICITATION AGREEMENT

This Confidentiality, Non-Competition, and Non-Solicitation Agreement (“Agreement”) is entered into this 8th day of January, 2008, by and between Under Armour, Inc. (together with its affiliates, the “Company”) and Suzanne Karkus (“Employee”).

EXPLANATORY NOTE

The Employee recognizes that the Employee has had and will continue to have access to confidential proprietary information during the course of his or her employment and that the Employee’s subsequent employment by a competitor would inevitably result in the disclosure of that information and, thereby, create unfair competition and would likely to cause substantial loss and harm to the Company. The Employee further acknowledges that employment with the Company is based on the Employee’s agreement to abide by the covenants contained herein.

NOW THEREFORE, for good and valuable consideration, the sufficiency and receipt of which are hereby acknowledged, the parties agree as follows:

1. Confidentiality. Employee acknowledges Employee’s fiduciary duty and duty of loyalty to the Company. Further, Employee acknowledges that the Company, in reliance of this Agreement, will provide Employee access to trade secrets, customers, proprietary data and other confidential information. Employee agrees to retain said information as confidential and not to use said information for self or disclose same to any third party, except when required to do so to properly perform duties to the Company. Further, as a condition of employment, during the time Employee is employed by the Company and continuing after any termination of the Employee’s employment with the Company, Employee agrees to protect and hold in a fiduciary capacity for the benefit of the Company all Confidential Information, as defined below, unless the Employee is required to disclose Confidential Information pursuant to the terms of a valid and effective order issued by a court of competent jurisdiction or a governmental authority. The Employee shall use Confidential Information solely for the purpose of carrying out those duties assigned Employee as an employee of the Company and not for any other purpose. The disclosure of Confidential Information to the Employee shall not be construed as granting to the Employee any license under any copyright, trade secret, or any right of ownership or right to use the Confidential Information whatsoever. In the event that Employee is compelled, pursuant to a subpoena or order of a court or other body having jurisdiction over such matter, to produce any Confidential Information or other information relevant to the Company, Employee agrees to promptly provide the Company with written notice of such subpoena or order so that the Company may timely move to quash if appropriate.

(a) For the purposes of this Agreement, “Confidential Information” shall mean all information related to the Company’s business that is not generally known to the public. Confidential Information shall include, but shall not be limited to: any financial (whether historical, projections or forecasts), pricing, cost, business, planning,

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operations, services, potential services, products, potential products, technical information, intellectual property, trade secrets and/or know-how, formulas, production, purchasing, marketing, sales, personnel, customer, supplier, or other information of the Company; any papers, data, records, processes, methods, techniques, systems, models, samples, devices, equipment, compilations, invoices, customer lists, or documents of the Company; any confidential information or trade secrets of any third party provided to the Company in confidence or subject to other use or disclosure restrictions or limitations; this Agreement and its terms; and any other information, written, oral or electronic, whether existing now or at some time in the future, whether pertaining to current or future developments or prospects, and whether accessed prior to the Employee’s tenure with the Company or to be accessed during Employee’s future employment or association with the Company, which pertains to the Company’s affairs or interests or with whom or how the Company does business. The Company acknowledges and agrees that Confidential Information shall not include information which is or becomes publicly available other than as a result of a disclosure by the Employee.

(b) The Employee shall promptly notify the Company if he has reason to believe that the unauthorized use, possession, or disclosure of any Confidential Information has occurred or may occur.

(c) All physical items containing Confidential Information, including, but not limited to, the business plan, know-how, collection methods and procedures, advertising techniques, marketing plans and methods, sales techniques, documentation, contracts, reports, letters, notes, any computer media, customer lists and all other information and materials of the Company’s business and operations, shall remain the exclusive and confidential property of the Company and shall be returned, along with any copies or notes that the Employee made thereof or therefrom, to the Company when the Employee ceases employment with the Company. The Employee further agrees to return copies of any Confidential Information contained on Employee’s home computer, portable computer or other similar device. Employee also agrees to allow the Company, upon reasonable belief and with appropriate notice, access to any home computer, portable computer or other similar device maintained by Employee, including but not limited to, for the purpose of determining whether said Confidential Information has been misappropriated. The Employee further agrees to promptly return all other property belonging to the Company upon the termination of Employee’s employment.

2. Non-Competition. Except as otherwise provided in this Agreement, without the prior written consent of the Company, the Employee hereby covenants and agrees that at no time during the Employee’s employment with Company and for a period of one (1) year immediately following termination of Employee’s employment with the Company, whether voluntary or involuntary, shall the Employee:

(a) directly or indirectly work for or engage in any capacity in any activities or provide strategic advice to Competitor Businesses. Competitor Businesses shall be defined as (i) any business that is involved in the manufacture, sale, development of fabrications or manufacturing methods, or marketing of: athletic apparel or footwear (e.g., Reebok, Nike, Adidas); sporting goods; tactical (military and/or law enforcement) apparel; hunting and fishing apparel; mountain sports apparel; accessories of such industries; or any business substantially similar to the present business of the Company or

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such other business activity in which the Company may substantially engage; and (ii) retail enterprises which sell products that compete with the Company’s products;