The National Institute of Standards and Technology (NIST) has a requirement at its Gaithersburg, MD campus for a 4K recirculating cryostat with optical access and microwave access. Please see attached... The National Institute of Standards and Technology (NIST) has a requirement at its Gaithersburg, MD campus for a 4K recirculating cryostat with optical access and microwave access. Please see attached Solicitation# 1333ND26QNB680374 and related attachments 1 (Statement of Work) , and 2 (Applicable Provisions and Clauses) for full details.