Type-9 shuttlecraft

The type-9 shuttlecraft (or Class-2 shuttlecraft) was an auxiliary vehicle used by Starfleet, designed for use as an embarked craft from starships and outposts.

A standard Stafleet issue type-9 shuttlecraft was 8.5 meters in length, had a hull composed of tritanium alloy and had a maximum speed of warp 4. However, as employed by the crew of USS Voyager, the type-9 was capable of high-warp engine performance, reaching significantly past warp 9, in 2372, upon the utilization a newly discovered form of dilithium, that could remain stable at a much higher warp frequency.

As with other Starfleet shuttles of the era, this vessel are typically outfitted with phasers and other weapon systems of various designs, although concurrent shuttle designs, such as the type-6 shuttlecraft, were only armed on a mission-specific basis.

From Memory Alpha -- the free Star Trek reference