Battery Strap/Hold Down?

I've ordered the FLM chassis (along with a pile of other parts) for an electric rustler. I'm wonder how others have secured batteries and electronics to the chassis or are there other parts for the chassis not pictured?

I read threw the other topic about battery straps, and came to the conclusion that nothing other then velcro type (g-maxx) straps is available.

Might have to custom make something... would love to see what others have done.