MIL-PRF-89049A, PERFORMANCE SPECIFICATION: VECTOR PRODUCT FORMAT (VPF) PRODUCTS, GENERAL SPECIFICATION FOR (15 DEC 2005)., This specification defines the format for all National Geospatial-Intelligence Agency (NGA) products based on a standardized implementation of the Vector Product Format (VPF). Feature and attribute requirements, and other information for individual products are contained in the applicable specification sheets (see 2.2.1). Additional specification sheets may be added in the future.