Material: Metal Dimensions: 8mm: Dimensions when overlapped 8*8*18mm; Dimensions when unfolded 20.2 x 8 x 12.4mm 10mm: Dimensions when overlapped 10 x 10 x 22.4mm; Dimensions when unfolded 25.3 x 10 x 17mm 12mm: Dimensions when overlapped 12 x 12 x 27mm; Dimensions when unfolded 30.7*12*19.7mm Color: Brass Quantity: 4 pieces Package Contents: 4*one hidden hinge 1.【High-quality material】: The hinge is made of durable material copper, which will not rust, is sturdy and durable. And can be used for a long time. 2.【Easy to install】: The cabinet hidden hinges are easy to use and easy to install. This product contains 4 hinges. 3.【Easy to use】: These invisible hinges are very easy to use and install. The opening angle and unique design ensure a better operating experience. 4. [Scope of application]: This hinge can be used for wooden doors, cabinet doors, light RV countertops or tables and many DIY projects. 5. [Ideal gift]: You can use these barrel hinges to make your own boxes as an ideal gift for friends and family.