Different specifications make it possible to meet different work requirements. The ergonomic design makes it very comcompatibletable to hold and non-slip. Exquisite and professional workmanship makes it very sturdy and durable. And the wide range of applications makes it very practical and useful. Made of high speed steel material, it is very durable to use. There are four specifications (5-7mm, 8-11mm, 10-15mm, 12-19mm) in this set. It can be used in living room, kitchen, bathroom, balcony, etc. all kinds of environments beautiful seam, simple and convenient. Item Name: Pressure Seam Steel Ball Material: High Speed Steel Quantity: 4Pcs Features: Double Head, Easy to Operate, Sturdy Size Details: 5-7mm: 11.5cm x 0.7cm x 0.7cm/4.53" x 0.28" x 0.28" (Approx.) 8-11mm: 12cm x 1.1cm x 1.1cm/4.72" x 0.43" x 0.43" (Approx.) 10-15mm: 12.8cm x 1.5cm x 1.5cm/5.04" x 0.59" x 0.59" (Approx.) 12-19mm: 13cm x 1.9cm x 1.9cm/5.12" x 0.75" x 0.75" (Approx.) Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 4 x Pressure Seam Steel Balls (5-7mm, 8-11mm, 10-15mm, 12-19mm)