Ready for 3d printing. Solid and hollowed version. 4 sizes
volumes solid: size 18 - 1318 mm3; size 19 - 1357 mm3; size 20 - 1395 mm3; size 21 - 1433 mm3;
volumes hollowed: size 18 - 761 mm3; size 19 - 787 mm3; size 20 - 812 mm3; size 21 - 838 mm3; thickness - 0,8 mm