Table schema:
CREATE TABLE table_2071644_1 (flange_width__mm_ VARCHAR, cross_section_area__cm_2__ VARCHAR)

Question: What is the flange width (mm) for cross section area (cm 2) 16.4?
SQL: SELECT COUNT(flange_width__mm_) FROM table_2071644_1 WHERE cross_section_area__cm_2__ = "16.4"