The breast pump flange inserts are made of silicone material, sturdy and useful, compatible with electric breast pumps and wearable breast pumps, simple and easy to replace, convenient to use. Safe, excellent, simple, convenient, sturdy, and practical.Features - Color: As Shown - Material: Silicone - Size: 4.60 x 4.60 x 3.40 cm / 1.81 x 1.81 x 1.34 in - Note: 13mm, 15mm, 17mm, 18mm, 19mm, 20mm, 21mm, 24mm - Made of silicone material, flange inserts are safe and practical, sturdy and durable, designed for long-term use - Smooth surface, no rough burrs, breast pump flange inserts are well-made and sturdy, gentle on skin, comfortable to use - Fine texture, easy to replace, safe and reliable, practical and high quality - Excellent performance, simple design, thoughtfully engineered for confident use - Compatible with wearable breast pumps and electric breast pumps, easy to use, providing added convenience Packing list: 1 x breast pump flange insert 24mm 1 x breast pump flange insert 21mm 1 x breast pump flange insert 20mm 1 x breast pump flange insert 19mm 1 x breast pump flange insert 18mm 1 x breast pump flange insert 17mm 1 x breast pump flange insert 15mm 1 x breast pump flange insert 13mm