Document

AMENDMENT NO. 1 TO RESTRICTED STOCK UNIT GRANT NOTICE AND RESTRICTED STOCK UNIT AGREEMENT

WHEREAS, capitalized terms not specifically defined in this Amendment No. 1 to Restricted Stock Unit Grant Notice and Restricted Stock Unit Agreement (the “Amendment”) have the meanings given to them in the Amended and Restated 2019 Omnibus Incentive Plan (as amended from time to time, the “Plan”) of Custom Truck One Source, Inc. (f/k/a Nesco Holdings, Inc., the “Company”) and the Existing Agreement;

WHEREAS, Participant listed below (“Participant”) was previously granted ______ Restricted Stock Units (the “RSUs”) pursuant to a Restricted Stock Unit Grant Notice (the “Grant Notice”) and Restricted Stock Unit Agreement (the “Agreement”) dated ______ (together, the “Existing Agreement”);

WHEREAS Section 9.6 of the Plan permits the Administrator to amend any Award without the consent of a Participant if the change does not materially and adversely affect such Participant’s rights under the Award;

WHEREAS, on April 28, 2025 (the “Amendment Date”), the Administrator approved an amendment to certain terms of the RSUs and the Existing Agreement as set forth in this Amendment including Exhibit A attached hereto; and

WHEREAS, the Administrator determined that Amendment does not materially and adversely affect the Participant’s rights under the Award.

NOW, THEREFORE, as of the Amendment Date, the Existing Agreement is amended as follows:

1.The “Vesting Schedule” section of the Grant Notice is hereby deleted and replaced with the following:

“Subject to the terms of the Agreement and Exhibit B attached hereto, the RSUs will vest in four substantially equal annual installments on each of the first four anniversaries (each such date, a “Vesting Date”) of the vesting commencement date set forth above (the “Vesting Commencement Date”), such that the RSUs will be fully vested on the fourth anniversary of the Vesting Commencement Date.”

“Incorporation of Terms of Plan. The RSUs are subject to the terms and conditions set forth in this Agreement and the Plan, which is incorporated herein by reference. In the event of any inconsistency between the Plan and this Agreement, the terms of the Plan will control, except as otherwise expressly provided in Section 2.1(b)(ii) and Exhibit B attached hereto.”

3.Section 2.1(a) of the Agreement is hereby deleted and replaced with the following:

4.“Subject to Section 2.2 hereof and subject to any potential reductions due to mitigation of any excise taxes under Section 4999 of the Code as may be set forth in any employment or other agreement between Participant and the Company, the RSUs will vest according to the vesting

schedule in the Grant Notice and Exhibit B attached hereto except that any fraction of an RSU that would otherwise be vested will be accumulated and will vest only when a whole RSU has accumulated.”

5.The additional provisions attached as Exhibit A to this Amendment are attached to the Existing Agreement as new Exhibit B.

6.This Amendment shall be and is hereby incorporated in and forms a part of the Existing Agreement.

7.All other terms and provisions of the Existing Agreement shall remain unchanged except as specifically modified herein.


CUSTOM TRUCK ONE SOURCE, INC.
By:
Name:
Title: