SIGNATURES
Dated: March 6, 2019
SOTER CAPITAL, LLC
By: /s/ Mary Ann Sigler
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Name: Mary Ann Sigler
Title: President and Treasurer
SOTER CAPITAL HOLDINGS, LLC
By: /s/ Mary Ann Sigler
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Name: Mary Ann Sigler
Title: President and Treasurer
PE SOTER HOLDINGS, LLC
By: /s/ Mary Ann Sigler
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Name: Mary Ann Sigler
Title: President and Treasurer
PLATINUM EQUITY CAPITAL SOTER PARTNERS, L.P.
By: Platinum Equity Partners III, LLC, its general partner
By: Platinum Equity Investment Holdings III, LLC, its senior managing member
By: /s/ Mary Ann Sigler
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Name: Mary Ann Sigler
Title: Vice President and Treasurer
PLATINUM EQUITY PARTNERS III, LLC
By: Platinum Equity Investment Holdings III, LLC, its senior managing member
By: /s/ Mary Ann Sigler
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Name: Mary Ann Sigler
Title: Vice President and Treasurer
PLATINUM EQUITY INVESTMENT HOLDINGS III, LLC
By: /s/ Mary Ann Sigler
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Name: Mary Ann Sigler
Title: Vice President and Treasurer
PLATINUM EQUITY, LLC
By: /s/ Mary Ann Sigler
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Name: Mary Ann Sigler
Title: Executive Vice President, Chief Financial Officer and Treasurer
Tom Gores
/s/ Mary Ann Sigler
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Mary Ann Sigler
Attorney-in-Fact
[Signature Page to Form 4]
