Gov't contracts often have a "Buy American" clause which requires them to buy from US companies or Trade Agreeement Act countries.
See FAR Subpart 25.11, and 52.225-1, 52.225-3, and 52.225-5.
See the bottom of this page and the links there-in
Subpart 25.11 – Solicitation Provisions and Contract Clauses
25.1101 – Acquisition of Supplies The following provisions and clauses apply to the acquisition of supplies and acquisition of services
involving the furnishing of supplies.
(a)
(1) Insert the clause at 52.225-1, Buy American—Supplies, in
solicitations and contracts with a value exceeding the micro-purchase
threshold but not exceeding 25,000 dollars; and in solicitations and
contracts with a value exceeding 25,000 dollars, if none of the
clauses prescribed in paragraphs (b) and (c) of this section apply,
except if--
(i) The solicitation is restricted to domestic end products in
accordance with Subpart 6.3;
(ii) The acquisition is for supplies for use within the United States
and an exception to the Buy American statute applies (e.g.,
nonavailability, public interest, or information technology that is a
commercial item); or
(iii) The acquisition is for supplies for use outside the United
States.
(2) Insert the provision at 52.225-2, Buy American Certificate, in
solicitations containing the clause at 52.225-1.
(b)
(1)
(i) Insert the clause at 52.225-3, Buy American--Free Trade
Agreements--Israeli Trade Act, in solicitations and contracts if --
(A) The acquisition is for supplies, or for services involving the
furnishing of supplies, for use within the United States, and the
acquisition value is 25,000 dollars or more, but is less than 180,000
dollars;
(B) The acquisition is not for information technology that is a
commercial item, using fiscal year 2004 or subsequent fiscal year
funds; and
(C) No exception in 25.401 applies. For acquisitions of agencies not
subject to the Israeli Trade Act (see 25.406), see agency regulations.
(ii) If the acquisition value is 25,000 dollars or more but is less
than 50,000 dollars, use the clause with its Alternate I.
(iii) If the acquisition value is 50,000 dollars or more but is less
than 80,317 dollars, use the clause with its Alternate II.
(iv) If the acquisition value is 80,317 dollars or more but is less
than 100,000 dollars, use the clause with its Alternate III.
(2)
(i) Insert the provision at 52.225-4, Buy American--Free Trade
Agreements--Israeli Trade Act Certificate, in solicitations containing
the clause at 52.225-3.
(ii) If the acquisition value is 25,000 dollars or more but is less
than 50,000 dollars, use the provision with its Alternate I.
(iii) If the acquisition value is 50,000 dollars or more but less than
80,317 dollars use the provision with its Alternate II.
(iv) If the acquisition value is 77,533 dollars or more, but is less
than 100,000 dollars, use the provision with its Alternate III.
(c)
(1) Insert the clause at 52.225-5, Trade Agreements, in solicitations
and contracts valued at 180,000 dollars or more, if the acquisition is
covered by the WTO GPA (see subpart 25.4) and the agency has
determined that the restrictions of the Buy American statute are not
applicable to U.S.-made end products. If the agency has not made such
a determination, the contracting officer must follow agency
procedures.
(2) Insert the provision at 52.225-6, Trade Agreements Certificate, in
solicitations containing the clause at 52.225-5.