Which of the following is a correct condition for gunned material test panels used for...

API Std 936 specifies in Section 6.6.1.1 that the test panels for pneumatic gunning must be cast to a minimum thickness of 2 inches with an acceptable tolerance:

"The minimum gunned thickness shall be 2 in. (50 mm), and the final thickness shall be within ±0.25 in. (6 mm) of the target."

— API Std 936, Section 6.6.1.1​

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