I have an 'Eclipse Blade E2 AutoCocker'
What Reg would i need >.< sorry im no good at this Technicle stuff.
High pressure (HP)
This type reg has about 850psi going into the gun as opposed to low pressure (LP) which has around 450psi.
Your E2 will run on LP but get a HP reg as you'll get a better recharge rate and therefore more stable performance.
So just in case you don't know it yet but you need a "1.1Litre (0.68Cu) HP fibre wrap bottle" which will screw straight into your gun.
That's pretty much the standard bottle for 80% of players