Gas pipe.
(28.6-25.5)/2 = 1.55mm wall thickness. More likely it's supposed to be 25.4, that would make the wall 16g, a common size for mild steel tubing.
@gbj_tester started
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Gas pipe.
(28.6-25.5)/2 = 1.55mm wall thickness. More likely it's supposed to be 25.4, that would make the wall 16g, a common size for mild steel tubing.