HVAC Dust / Air Filter Element Cartridge

P/N: 51900 (Written on box with marker)

10.3" Inches Wide x 26.6" Inches Long

New old stock surplus, Surplus inventory stock from a closed business, In the original box.  This box contains the filter only, No additional accessories.

Unit received as part of a larger case lot of other new old stock filters, Mostly Clark's, However this unit has no numbers, insignias or other identification marked anywhere on the exterior, the only numbers are the 51900 written on the exterior of the box. It's uncertain if this unit is also a Clark, or an unbranded replacement version. 

This auction is for the exact unit shown.