Phone Skope Dilemma

Wanting to buy one. Not sure which one I should get. The model with the adjustable lens cap or the cap that only fits my Swarovski spotting scope. Let me here your opinion please. Makes sense to get the adjustable one so that it can be used with bino's also. But not if its a sloppy fit in them.

I have reviewed and tested both.
for SURE!
Go with the one that fits your scope.
The adjustable one works ok, but not great.