How big should a RBTA for two clowns

[t11t5]

I have a BTA thats only 3" or so across fully opened. If its not big enough how big should it get? Im looking at 2 of the three stripe maroon clown....

 

[t11t5]

anyone

 

[Flippers4pups]

Can't help you there. Never had luck them. But my clowns loved a toadstool leather!

 

[garygb]

For BTAs, I agree with bobby.