Hi @ajaysahoo

Apologies for delayed response.
Trading series of NSE stock represent the type of trading allowed for respective stock. Please refer for more info

https://www.tickertape.in/blog/nse-stock-series-what-do-they-mean-and-which-category-is-for-you/#:~:text=This series stands for equity,on the same trading day.

Thanks & Regards,
SmartAPI team