Micro Transmitter and receiver help

[ZZ NOS]

Hey all,

I'm not good on the technical stuff. I'm trying to find out the specs of a very basic transmitter and receiver. But they need to be small mainly the receiver. Coz i'm planing a mod that could use a micro receiver, the receiver needs to be able to fit into the top of the ZipZap.

If any of you are able to help me with specs and parts i'll need, thank you.
If i do get specs and info, i'll tell you what it is when i have finished building.

ZZ NOS