What is the eligibility for politechnic cours?

There are different eligibility criteria with subject to different institutions. Most require 10th pass, some may require 10+2 science and maths or 10+2 years of ITI. These criteria often change from course to course also.
You can see top 25 polytechnic colleges in India : http://www.indiaeducation.net/top-colleges/polytechnic/

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