Two knives. One design.
As related to size, the I knife configuration is designed to be more maneuverable when dissecting with a smaller cutting electrode compared to the O knife.
This configuration incorporates a ceramic tip which is designed to insulate the distal end of the knife that limits energy reaching deeper areas of the mucosa.
The Medtronic ProdiGI™ multi-functional electrosurgical knife has been designed for the endoscopist who needs to switch from one cutting technique to another without exchanging devices. This electrosurgical knife combines two of the most common knife geometries into one design.