Upgraded arp 556

Hi I'm selling my G&G 556 it's been fully upgraded but I can't remember what it has been upgraded with as I bought it second hand but works perfectly I'm selling due to not using it anymore it's a great gun with good range and good rate of fire it's light. It's been used a good number of times has done me great in games. Has a battery extender. Custom paint job. Comes with 1 low cap mag and grip but doesn't come with original box. Happy to post and happy to send videos of it working.