Found crawling on apartment kitchen floor. Length was measured to top of its head, with it's face tucked under. With the "nose" stretched out it was 21-22mm. Very active, it startled me by crawling on my hand and I instinctively threw it off. I thought I had killed it and it played dead rather impressively for several minutes, exuding copious amounts of "oil." But it resurrected itself and crawled away vigorously, outdoors this time. My first Oil Beetle, a female, I think.