National Stock Number
4240-00-999-0420
National Stock Number (NSN) 4240-00-999-0420, or NIIN 009990420, (hood,chemical-biological mask) was assigned December 21, 1965 in the Federal Logistics Information System (FLIS). This NIIN is Available for Manual Assignment. This NSN does not replace any other NSNs.
There are 2 manufacturer part numbers associated with this NSN. None of the associated part number(s) are considered obsolete. The manufacturer part numbers were originally supplied by one supplier. Today, one supplier is listed as an Active supplier for this NSN. Of the active suppliers, there are no suppliers that are deemed design controlled or valid supply parts. ISO Group has several sources of supply for this NSN.
This part number has not been procured by the US Government in over 5 years.
There has been very little demand for this national stock number. The demand for this NSN originated from less than 5 countries. Based on a planned procurement review by the Primary Inventory Control Activity (PICA) on Oct 24, 2013, this NSN's acquisition method was noted as: Suitable for Competitive Acquisition. (Potential sources shall include dealers/distributors.) The Government has unlimited rights to the technical data, and the data package is complete. Valid AMCs: 1 and 2.
This NSN is assigned to Item Name Code (INC) 28008. [A COVERING FOR THE HEAD, NECK, AND SHOULDERS, DESIGNED TO FIT OVER A CHEMICAL-BIOLOGICAL MASK WITHOUT INTERFERENCE WITH WEARER'S VISION OR WITH AIR CIRCULATION THROUGH THE FILTERING AND OUTLET MECHANISM OF THE MASK. IT PROVIDES ADDITIONAL PROTECTION AGAINST CHEMICAL AND BIOLOGICAL TOXIC AGENTS.]. This item does not have a critical feature such as tolerance, fit restrictions or application. Nuclear hardness properties have not been determined (not valid for input). There is no information in the HMIRS; however, the NSN is in an FSC in Table II of Federal Standard 313 and an MSDS may be required by the user. The requirement for an MSDS is dependent on a hazard determination of the supplier or the intended end use of the product. NSN 4240009990420 does not contain precious metals.
This NSN is associated to Schedule B 6506100090: safety headgear, whether or not lined or trimmed, n.e.s.o.i.. The Schedule B End Use is listed as apparel,household goods-nontextile. NAICS classification category 339113: surgical appliance and supplies manufacturing.
This information was last updated on Aug 01, 2025.