LIMITED POWER OF ATTORNEY

The undersigned, a director of MRC Global Inc. (the ?Corporation?),
who will thereby be subject to the reporting obligations of Section 16
of the Securities Exchange Act of 1934, as amended (the ?Act?), with
respect to securities of the Corporation, hereby constitutes and
appoints, with full power of substitution or revocation, each of Daniel
J. Churay and Ann D. Garnett, or such attorney?s-in-fact substitute or
substitutes, as the undersigned?s true and lawful attorneys-in-fact and
agents to execute and file for and on behalf of the undersigned Forms
3, 4 and 5 with the Securities and Exchange Commission (the ?SEC?), and
to perform all acts necessary in order to execute and file such Forms
3, 4 and 5, as he or she, as applicable, shall deem appropriate. The
undersigned hereby ratifies and confirms all that said attorneys-in-fact
and agents, or such attorney?s-in-fact substitute or substitutes, shall
do or cause to be done by virtue hereof.

The undersigned acknowledges that the foregoing attorneys-in-fact,
in serving in such capacity at the request of the undersigned, or such
attorney?s-in-fact substitute or substitutes, are not assuming, nor is
the Corporation assuming, any of the undersigned?s responsibilities to
comply with Section 16 of the Act. This Limited Power of Attorney shall
remain in full force and effect until the undersigned is no longer
required to file Forms 3, 4 and 5 with respect to the undersigned?s
holdings of and transactions in securities issued by the Corporation,
unless earlier revoked by the undersigned in a signed writing delivered
to the foregoing attorneys-in-fact.

This Limited Power of Attorney is effective as of October 31, 2017,
and any previous power of attorney issued by the undersigned for the
purpose of executing and filing Forms 3, 4 and 5 with the SEC with
respect to holdings of and transactions in securities issued by the
Corporation is hereby revoked (without affecting the effectiveness of
any such power of attorney prior to the date hereof).


/s/ Deborah G. Adams
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 Deborah G. Adams