NCO 23 has a requirement for Bayer Contrast Injectors Maintenance across multiple locations within VISN 23. Â This is a total SDVOSB set aside. Â FOR CONSIDERATION ALL QUESTIONS MUST BE RECEIVED 72 HO... NCO 23 has a requirement for Bayer Contrast Injectors Maintenance across multiple locations within VISN 23. Â This is a total SDVOSB set aside. Â FOR CONSIDERATION ALL QUESTIONS MUST BE RECEIVED 72 HOURS BEFORE DATE STIPULATED IN BLOCK 8 OF THE SF1449 FORM. EMAIL ALL QUESTIONS AND RESPONSES TO jennifer.Watkins-schoenig@va.gov and joshua.Imdacha@va.gov