48 CFR § 52.228-2 - Additional Bond Security.
As prescribed in 28.106-4(a), insert the following clause:
(a) Any surety upon any bond, or issuing financial institution for other security, furnished with this contract becomes unacceptable to the Government;
(b) Any surety fails to furnish reports on its financial condition as required by the Government;
(c) The contract price is increased so that the penal sum of any bond becomes inadequate in the opinion of the Contracting Officer; or
(d) An irrevocable letter of credit (ILC) used as security will expire before the end of the period of required security. If the Contractor does not furnish an acceptable extension or replacement ILC, or other acceptable substitute, at least 30 days before an ILC's scheduled expiration, the Contracting officer has the right to immediately draw on the ILC.