Body: 18×3.5×3.5 cm with two 1.5 cm holes
for 20 cm long rods (1.5×1.5 cm) positioned at a 90° angle.

Above that, a 6 cm long wooden wedge (1.2 cm wide,
tapering from 1.4 to 0.8 cm) clamps the two rods together.

Each rod is tipped with a 4 mm long sharpened nail.