Inno Sense Medium Port Inno Sense Medium Port bits are made of an elastic plastic and are slightly harder than the Inno Sense flexi soft bits. Inno Sense Medium Port bits are slightly flexible and have a tongue port. The plastic of the Inno Sense bits is FDA approved, the material is non-toxic and contains no plasticizers. 2½ & 3 Ring Bit: A 2½ & 3 Ring Snaffle is also called a Pessoa bit and can be recognized by the extra rings on top and at the bottom of the regular bit rings. The top ring is used to attach the cheekpiece and the bottom ring the rein. When using the rein, the top ring will tilt forward and create leverage. The strength of the impact is determined by the type of mouthpiece, material and number of rings. A 2½ ring snaffle is therefore less effective than a 3 ring snaffle. Straight mouthpiece features: A straight mouthpiece consists of 1 piece and gives pressure on the tongue, layers and lips. The shape and thickness of the mouthpiece determine where the pressure will be in the mouth. A straight mouthpiece with a tongue port gives more pressure on the layers and keeps the tongue free. The straighter and thicker the mouthpiece, the more pressure on the tongue.