PDI W-hold Chamber Packing.
This rubber packing is made of NTR 50 deg.
It's a little softer than Marui original (60 deg)
Also put a W shaped nub inside to spin a HOP.
Its W catches a BB top widely,so BB will be spined well.
Outside,we add 2 ring shape. It'll be sealed well for airtight.
So this rubber will make highly FPS.
About shipping cost:
This parts is not so heavy,so almost no changable for the shipping cost.
But our system,when you purcahse a lot,the shipping cost will be expensive.
Giving order, we fix the cost to correct price by 2nd e-mail reply.
Don't worry about it. If you feel an expensive the cost,please tell us about your cancel.
We accept anytime.