The major difference between Black and Decker BDH2000L and BDH2000PL are as follows:
BDH2000L vs BDH2000PL
images from manufacturer

Suction Power:
The BDH2000L has a suction power of 24 air watts versus 35 air watts on the BDH2000PL.

Nozzle Design:
The nozzle on the BDH2000L allows you to rotate it to the left or right whereas the BDH2000PL has a pivoting nozzle that can be pivoted up and down.
And the BDH2000PL nozzle is wider.

Dust Cup Design:
The BDH2000PL has the opening at the side whereas the BDH2000L has the opening on top and bottom.

Capacity:
The BDH2000L has a bin capacity of 20.6 oz. whereas the BDH2000PL can holds 15 oz..

Warranty:
The BDH2000L carries a 3 year limited warranty whereas the BDH2000PL is backed by a 2 year limited warranty.

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