TPU fidget ring.

Spinner will fit on Ring after print.

I printed with Cura and these resizes are approximate
Ring
Size ------ Scale to
3 ---------- 62.78%
3.5 ------- 64.57%
4 --------- 66.37%
4.5 ------- 68.16%
5 ---------- 69.96%
5.5 ------- 71.75%
6 --------- 73.77%
6.5 ------- 75.78%
7 --------- 77.58%
7.5 ------- 79.37%
8 ---------- 81.61%
8.5 ------- 83.41%
9 ---------- 85.20%
9.5 ------- 87.00%
10 ---------88.79%
10.5 ------ 90.58%
11 -------- 92.38%
11.5 ------ 94.17%
12 -------- 95.96%
12.5 ------ 97.76%
13 -------- 99.55%
13.5 ----- 101.35%
14 -------- 103.14%
14.5 ----- 104.93%
15 -------- 106.73%
15.5 ----- 108.52%
16 -------- 110.31%
16.5 ----- 112.11%
17 -------- 113.90%
17.5 ----- 115.70%
18 -------- 117.49%
18.5 ----- 119.28%
19 -------- 121.08%
19.5 ----- 122.87%