I did run it slow and seemed ok but worried it would wear the ballnut fast .
Nope that ballscrew was the only one not from Fred , I ordered it in the EU to save time but wishing I hadn't now!
The seller is saying "For a ballscrew the external outer diameter is a totally unimportant dimension, because it connects to the ballnut with balls" which kind of makes sense but why call it a 16mm screw then. And Fred's are 16mm within 0.01mm ...