Number of layers (specification):

Two-layer large-black [lengthened]]

Two-layer medium-black [lengthened]]

Two-layer large-white [lengthened]]

Two-layer medium-white [lengthened]]

Two-layer large-black [standard]]

Two-layer medium-black [standard]]

Two-layer large-white [standard]]

Two-layer medium-white [standard]]

Three-layer large-black [lengthened]]

Three-layer medium-black [lengthened]]

Three-layer large-white [lengthened]]

Three-layer medium-white [lengthened]]

Three-layer large-black [standard]]

Three-layer medium-black [standard]]

Three-layer large-white [standard]]

Three-layer medium-white [standard]]