Pretty sure they should all have the black rubber washer on the screw inside of the hosel. Normally if you remove the entire shaft and turn the head upside down, the screw stays in place, held by the rubber washer. If the screw falls out, you have lost the washer and I would think it could affect your ability to keep the screw in place and hold properly. Call customer service and ask for sure. They can give you expert advise on this topic.

The 910, 913, 915 did need the washer or the screw fell out. The TS and TSI the screw is different and will not fall out. I have seen 1 new TS and 3 new TSI that had no rubber washer. And have seen some other sites where the TS series with people talking about no washer

Did not realize they did. Never had a reason to take the screw out.