Looks to be 0.030" standard. BE SURE and coat the threads with something before re-installing it. Never-Seize is best, but 2 drops of motor oil is WAY better than nothing.
There is no external oil filter on the Dash. So it's important to change your oil regularly... while the engine is HOT ! Huslter makes that easy and pain-free with the drain hose setup. Frequent changes (I'm thinking every 30 hours OR once every year; which ever comes first) means that the extra cost of expensive "super oils" is probably money down the drain.
Hope this helps.