K&N HP vs PS Oil Filters

[HTSS_TR]

Spin on HP series oil filters have the nut at the dome end for easy remove/install, the PS series don't have the nut. Other than the nut, what are the other differences ?

What are the differences between the HP series and PS series for the cartridge oil filter ? Since cartridge oil filters don't have the nut then there must be some differences between the 2 series. What are they ?

K&N PS-7002 cartridge oil filter

K&N HP-7002 cartridge oil filter

 

[Jim Allen]

I believe it's efficiency. Look real close on the website. I think I found a difference in efficiency. Dang me that I didn't write it down but I saw this question answered somewhere.

 

[Rolla07]

HP=better filtering media. Better efficiency like Jim said. Think its 99% compared to 90% (dont know exact numbers. PS is said to be high flow thus lower efficiency i suppose.