What is the minimum stress grade for a support post?

windy city oil field, karamay, xinjiang, China

Laying plastic pipes drainage to drain the water around the house of drainage system

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Worker in a carpentry shop measures plywood for cutting

Apartment Fusebox Installation by Caucasian Electrician in His 40s. Residential Home Electric System Theme.

Joyful young man construction worker holding mobile phone and smiling while standing by the table with laptop