side barrier dimensions
 

Is there anywhere where the manual describes the dimensions of the side railing? not just the top and bottom bar types and height or the support bar types, but where along the railing the support bars are placed and what keeps balls from going through between the top and bottom bars.

Re: side barrier dimensions
 

I can answer this part of the question:






...nothing...

What's to stop them from leaving the field?
 

Initially, it is inertia that prevents the balls from going between the top and bottom bars.

Look out, ticketholders!
 

But, once accelerated to a constant velocity, those soccer balls will tend to stay at that velocity until acted upon by an outside force.

Such as the VIPs in the front row....

:)