The GUPPY comes in ONLY one size - 4.25 in / 10.2 cm in diameter. Many new users are surprised at how few stems it can hold and equally surprised at how many it can hold.  With repeated use, you will discover its capabilities.
At minimum it can fit a 2-3" opening using half a GUPPY- rolled like a crepe or as wide as a 10" vase  opening.  It is really the 'stems canopy' resting in the lip of the vase opening.
To arrange 'Grand Hotel/Wedding' size diplays we have an EXCLUSIVE GUPPY POD system.  A video is in the Demonstration Page.   The POD system technique and the GUPPYS ability to fit ' watertubes' allows even more daring designs and installations.   One size is all you need!