Mga bros and sis,

I was scouring different auto supplies in Las Pinas, Pasay and Banawe to find a replacement valve seal for my Mazda 323.

Everyone of them only has the NOK brand kaso naguluhan ako dun sa Pasay kasi may dalawang klase daw yun. The generic one that costs 50 each and the other one that costs 180 each and the only difference is that guaranteed daw yung isa dahil may specific part number and yun daw talaga and para dun and sure na matibay

My question now is how do you determine a genuine valve seal ng NOK? Naguluhan lang ako sa explanation nya kasi hehehe