7-1/2" long refillable precision plastic pen clock oiler. Has a 3-1/4" long metal needle for those hard to reach places. Filled with 1/4 ounce of high quality semi-synthetic clock oil, enough to oil about 50 clocks. Just squeeze the reservoir to apply a small drop of oil to the gears’ pivots (the thin ends of the gears) where they extend through their bushings (holes in the plates), on both the back plate and front plate, and a tiny dab between the ratchet wheel and plate, and nowhere else.