The Linx foam filter has been known by various part numbers, including:
Fits cordless stick and hand vac models: BH50010, BH50010CA, BH50015, CH20110 and BH50030.
This filter is now FOAM ON BOTH SIDES.
It originally was foam on one side and a different material on the bottom. All new versions of this filter are foam on both sides of the filter.
This genuine Hoover Linx replacement filter is made for the Hoover Platinum Stick and Hoover Hand Vacs that use Hoover part number 410044001, AH40001, 001331007 or 902185003.