Lightweight aluminum rims without eyelets often have burrs on the nipple seat. These increase the workload when lacing tremendously since the ridge has to be leveled from the nipple and increases friction. For a better fit of the nipple into the rim found them stayed, the spoke holes to countersink before with a deburring something.
Material: aluminum, steel
Note: Color of the handle may differ depending on the whim of tune ;-)