This is a sole-source solicitation for a Mine Roof Simulator (MRS) Upgrade, with the government intending to award a Firm-Fixed-Price purchase order to MTS Systems Corporation under FAR 6.103-1. However, the government will evaluate timely responses from other responsible sources to determine if another source can meet the requirements. Interested offerors must submit a signed quotation including pricing, acknowledgment of amendments, representations and certifications, and compliance information, and must be registered in SAM. All correspondence must be submitted in writing to the contracting officer.