PDI AEG W Hold Chamber Packing Hop Up Bucking - 70 Degree (GG08-04)

PDI rubbers have two ribs for improved air seal. The design has two nubs with a channel in between, which helps center the BB in the barrel for more consistent hop application.

From PDI:

• Compact, but it has high power
• This is the new model packing of PDI.
• It has two ring ribs on the outer surface and improved air tightness.
• And more, it has "W hold ledges".
• Two ledges in the packing are steady of the BB's trajectory.
• It is made of nitrile rubber(Hs50) and has high oil and abrasion resistance.
• You can use it all season!