These cesti are fitted with the claws of an umber hulk. One umber hulk yields two pairs of cesti. After construction, the 4th level wizard spell Dig is cast on each of the cesti. This enables the wearer to dig like an umber hulk: 10 feet per turn through solid stone and 60 feet per turn through soft earth for 6 turns (1 hour). The tunnel created is large enough to accommodate a man-sized creature without stooping. A complete pair must be used to achieve this rate of digging. If a single cestus is used, the rate of digging is 1/2.
These cesti are also deadly against earth elementals. They give the wearer a + 2 bonus to hit and deal 2d6 + 2 damage per successful hit (in addition to any strength bonus). They also count as a + 2 magical weapon for determining effectiveness against creatures with weapon immunity.