Hey there! 
I am new to this forum and new to forum's in general. 
My daughter just got three baby ferrets last week. 
We take them out everyday to play in her room. I have used cardboard to section off her room so it is ferret proof. 
I want to buy one of the play pens so we can use that instead in our dining room.
But I can't find one online that has very small bar spacing. 
These babies are only around 6 to 8 weeks old and I am so scared of them squeezing through the bars. 
Any help would be appreciated for a link to the proper enclosure as I have been looking online but the bar spacing is too big!
Any other tips would be welcome as well as these are our first ferrets!

Hello and Welcome to the forum!
I have the Marshall 8 panel playpen that you can buy a top and bottom for. I also recently bought one of the soft sided collapsible pens. They are made of nylon and mesh. The top and bottom zip on. You can get the Marshall's from ferret.com and I bought my soft sided from EBay. 

 
Fuzzbutts Rule!

Thank you for responding! 
It says the spacing on that one is 1".
I'm super worried about that because they are super tiny?! And I feel they could get through 1" spacing?

Personally I prefer the soft sided playpen. What is the spacing of the bars in their cage?

 
Fuzzbutts Rule!

Hi and welcome.  
I've never had a ferret escape from a Marshall's or similar playpen, but I've never had babies in them.  1 inch is the maximum spacing for ferrets. Some of mine can still get thru a 1 1/2 inch gap under a closet door as adults.

THE DOOKS OF HAZARD

I have the marshall play pen for my kids when we travel.   It works great....even when they were babies.

Marshall Play Pen.  You can purchased some extra panels to make it bigger.  I  have the mat that goes on the bottom of the playpen, also.

I hope this helps.

https://www.ferret.com/item/marshall-ferret-playpen-8-panel/650717/