250 uL Micro-Insert with Mandrel Interior & Polymer Feet, 29*5.7mm, suit for 11mm snap vials, Economy package: 250uL Conical Micro-Insert, 31*5.7mm, suit for 11mm snap vials: 250 uL Conical Micro-Insert, 31*5.7mm, suit for 11mm snap vials, Economy package: 300 uL Micro-Insert, 31*6mm, Clear, Flat Bottom, suit for 11mm snap vials