DaveyDitzer Loc: Western PA

Is the RRS system compatible with Arca Swiss?

amfoto1 Loc: San Jose, Calif. USA

I suspect you bought a "universal" plates that don't have anti-twist features. You will probably find that plate on the bottom of the camera will loosen frequently when you're trying to work with it. That can lead to a disaster, if you don't keep a close eye on it.

A better solution is a "fitted" camera plate, such: https://www.amazon.com/Acratech-Quick-Release-Plate-Camera/dp/B00GJBPOFA/ref=sr_1_3?dchild=1&keywords=d7100+arca+plate&qid=1614372413&s=electronics&sr=1-3

Notice the "tabs" designed to wrap around the base of the camera, so that the weight of the lens can't possibly cause the plate to slip and loosen.

You mention a Tamron 150-600 G2 lens... doesn't it have a built-in Arca-compatible dovetail, right in the tripod mounting foot? Even if it does, you still might want a longer plate to be able to slide it farther forward or backward than is possible with the built-in dovetail.

Does that lens plate also have some sort of anti-twist feature? It might be a tab that sticks up alongside the lens' tripod mounting foot... or it might be a second screw or a pin that somehow interfaces with the based of the tripod mounting foot. If the plate doesn't have any sort of anti-twist feature built in, it's possible to add one.... drill and tap a hole to thread a second screw into the foot, for example.

imagemeister Loc: mid east Florida

You know, there are TOOLS that you can use to tighten a single attachment screw with - but many people are too lazy for this.
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