The wearable breast pump flange inserts kit are made with silicone material, useful and durable, serving for long time, suitable for wearable breast pump, electric breast pump, simple to replace, simple and convenient to use. Safe and excellent, universal and practical. Features -Color:Transparent -Material:Silicone -Size:6.00X6.00X1.50cm/2.36X2.36X0.59in -Size:4.80X4.80X3.00cm/1.89X1.89X1.18in - Note: 13mm, 15mm, 17mm, 19mm, 21mm, compatible with s12 wearable breast pump - Made of silicone material, durable and excellent, safe and useful, breast pump flange inserts kit could be used for long time. - Smooth surface, without burrs, not worry about hurting your hands or skin, safe and useful. - Could be used for electric breast pump, wearable breast pump, simple and convenient to use. - Useful function, reasonable design, useful and safe, you could use flange inserts kit with peace of mind. - Simple design, wonderful workmanship, excellent performance, could be used for wearable breast pump accessories. Package list: 1 x breast pump flange insert 21mm 1 x breast pump flange insert 19mm 1 x breast pump flange insert 17mm 1 x breast pump flange insert 15mm 1 x breast pump flange insert 13mm 2 x duckbilled valves 2 x silicone diaphragms