How to eliminate unnecessary fractional number from search?

Hello! There is a set of strings of this kind:

38.3 x 26 x 2.9 cm
34,54 x 24,15 x 2,39 cm
29,8 x x 20,61 of 2.08 cm
41,95 x 27,9 x 2,78 cm

I was using something like Internet has made finding numbers (this is the smallest size - thickness)
(?<![\w\d]) 2(?![\w\d])|(?<![\w\d])x 2(?![\w\d])|(?<![\w\d]) 2(?![\w\d])(?=.*\bсм\b)|(?<![\w\d])x 2(?![\w\d])(?=.*\bсм\b)|(?<![\w\d])x2(?![\w\d])|(?<![\w\d])x2(?![\w\d])(?=.*\bсм\b)


But I can't do to I have missed the line where this number is greater than 2,5 (2.5), i.e. in this example, these lines superfluous:

38.3 x 26 x 2.9 cm
41,95 x 27,9 x 2,78 cm
March 19th 20 at 08:52
1 answer
March 19th 20 at 08:54
Solution
https://regex101.com/r/75UKFK/1
x ([01][.,]\d+|2[.,]([0-4]\d*|5)) cm

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