Very IMPORTANT READ THIS!
this spring is one of the hardest springs on the market and should not be bought unless you have the following:
1.) jbu aluminum piston (full teeth) with no teeth
2.) reinforced steel teeth for jbu piston (x2)-(just incase of wearing out)
3.) systema super-torque gear set
4.) 8mm reinforced steel gearbo shell!
5.) metal spring guide with ball bearings
6.) 8mm bushings and shims
7.) area 1000 aluminum poston head or systema silent head set
8.) systema non-bore up cylinder
9.) src aluminum nozzle for your gun
Then last you should buy 2 echo 1 grease sets and use it after every 1500 rounds fired, you should use the same bb's that came with your gun, you should use a 6.02mm+ barrel no smaller or else the bb could blow-up, you should use .25g+ airsoft gi bb's (or your guns manufacturers bb;s)
or else the bb's could jam and mess up your gun. then last the reason why you need the .25g bb's or higher is because the ones below .25 grams would be easier for the wind to push out of the way...
it would be wise to never-ever use full-auto for more than 5 seconds every hour because every time you would use full-auto the gun wears out a lot faster... Try TO USE SEMI/SINGLE SHOT AS MUCH AS YOU CAN! or use full - auto like this...
3 second bursts with 2 second stopping time
if you follow these instructions your gun will last 30% longer and with the non-full auto it would last another 40% longer....
THATS 70% LONGER THAN STOCK - GUNS/UPGRADED GUNS WHEN YOU DONT USE FULL AUTO AND UPGRADE!