Max Rainwell shows you the modification he did to the stock of the ASG-ICS Airsoft Hera Arms CQR. This mod allows you to change batteries without the need for a tool. This is a very handy mod when you need to change batteries in the middle of a firefight, letting you back into the fight quickly as you can change batteries faster... "A mod to fit and change the battery in the Hera CQR stock without any tool."