Question on Mag tube extention

[dingus]

How long a tube extention do i need now my 870 rem is sporting a shorter 18.5 inch barrel. I dont want the tube longer than the barrel.
I should know this but dont want to order one thats to long

Any ideas on a good brand to buy would be Ex to.
Its got a knox folder copstock and im getting a knox forend so thought i should get and Mag tube extention at the same time then im done

 

[RePete]

You are looking at a 7 shot (+2).

 

[badboybeeson]

i have a new remington 7shot and spring forsale for $50 if you intrested
bbb

 

[dingus]

Thanks RePete!
bbb I got some other stuff im ordering from my Contact so will just get the 7 rd extention from him at the same time to save on shipping.
thanks tho!