SIGNATURES
Dated: March 18, 2019
SOTER CAPITAL, LLC
By: /s/ Justin Maroldi
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Name: Justin Maroldi
Title: Assistant Secretary
SOTER CAPITAL HOLDINGS, LLC
By: /s/ Justin Maroldi
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Name: Justin Maroldi
Title: Assistant Secretary
PE SOTER HOLDINGS, LLC
By: /s/ Justin Maroldi
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Name: Justin Maroldi
Title: Assistant Secretary
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/ Justin Maroldi
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Name: Justin Maroldi
Title: Assistant Secretary
PLATINUM EQUITY PARTNERS III, LLC
By: Platinum Equity Investment Holdings III, LLC, its senior managing member
By: /s/ Justin Maroldi
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Name: Justin Maroldi
Title: Assistant Secretary
PLATINUM EQUITY INVESTMENT HOLDINGS III, LLC
By: /s/ Justin Maroldi
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Name: Justin Maroldi
Title: Assistant Secretary
PLATINUM EQUITY INVESTCO, L.P.
By: Platinum Equity Investment Holdings IC (Cayman), LLC, its general partner
By: /s/ Justin Maroldi
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Name: Justin Maroldi
Title: Assistant Secretary
PLATINUM EQUITY INVESTMENT HOLDINGS IC (CAYMAN), LLC
By: /s/ Justin Maroldi
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Name: Justin Maroldi
Title: Assistant Secretary
PLATINUM INVESTCO (CAYMAN), LLC
By: /s/ Justin Maroldi
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Name: Justin Maroldi
Title: Assistant Secretary
PLATINUM EQUITY INVESTMENT HOLDINGS, LLC
By: /s/ Justin Maroldi
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Name: Justin Maroldi
Title: Assistant Secretary
PLATINUM EQUITY INVESTMENT HOLDINGS III MANAGER, LLC
By: /s/ Justin Maroldi
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Name: Justin Maroldi
Title: Assistant Secretary
PLATINUM EQUITY, LLC
By: /s/ Justin Maroldi
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Name: Justin Maroldi
Title: Assistant Secretary
Tom Gores
/s/ Mary Ann Sigler
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Mary Ann Sigler
Attorney-in-Fact
[Signature Page to Form 4]
