Yikes...I've 3/4 finished a 69cc (80) kit, and still have NO IDEA what this thing is. I got the motor from boysgofast in Calgary AB, and honestly, so far I have found two parts to be missing. The "half-moon" metal backs, and the fuel stop-cock. I am assured they are on the way. But what on earth is THIS thing? It's in their Ebay picture, and trust me, I have been perusing you folks' vids and instructions for two days now, and cannot see it ever being used, or even shown. It looks to my truck-driving eyes like some kind of "one-size fits all" drain plug for a large oil pan! LOl...any help please?