some workshops say that AL4 uses 1 pce. and DPO 2pcs. - according to our findings this info is wrong. Both use only 1 pce. of this oil seal. The OE source for the oil (metal clad) seals has changed the design. The former metal/rubber (FPM) design is no longer produced by them and is also not used by the OE-transmission-manufacturer any longer. The new design is a fully rubber (FPM) coated black oil seal. For more info check our product information "IDS-DPO/AL4-Oil Seals". Using the "old design" is no problem.