Assimilation tubule

From Memory Alpha, the free Star Trek reference.

A drone uses assimilation tubules on an Enterprise-E crewman (2373).

Assimilation tubules were a pair of flexible needle-like devices that extended from the wrists or fingers of Borg drones. These tubules initiated the assimilation process by injecting Borg nanoprobes into a victim's bloodstream, and were capable of penetrating any armor or energy shielding known to the Federation. Assimilation tubules also allowed drones to interface with technology. (VOY: "Scorpion")

In their first appearance and in "Scorpion, Part I", the assimilation tubules appeared to be rigid, talon-like weapons; however, in later appearances on Voyager, the tubules seemed to be flexible objects, more along the lines of "tubules". This may indicate that they could stiffen depending on function.