I know they are 4" diameter, but what is the length? Can't find an EBay listing with the length and I want to think this through before I buy.

Thanks!
Sprite Reviewed by Sprite on . Quick question for someone who has a Pyrex tube--how long is it? I know they are 4" diameter, but what is the length? Can't find an EBay listing with the length and I want to think this through before I buy. Thanks! Rating: 5