Traveling with a lightspeed sunshade

[BabelFish]

My family will be traveling shortly for some beach-time and wanted to bring along our lightspeed sunshade. Reading online it seems that each airline treats these differently. I would like to know how best to travel with this item. I understand the 50 linear inch for carry-on and I believe this item is right around that limit (packs down to ~40" x 5" x 5").

Would southwest allow this as a carry on? 

Would southwest allow this as a checkin item without odd-size charge?

Should there be any issues with tsa at mdw for this item as carry on?

Thanks!

Lightspeed Outdoors Quick Cabana Beach Tent Sun Shelter, Blue Light... https://www.amazon.com/dp/B005LGV2PA/ref=cm_sw_r_sms_awdo_yDdLzbDKZ9BEN

[BabelFish]

We are leaving for the airport tonight at 2am. 😞 

Any help would be wonderful. Thanks

[CareforNOLA]

You can check baggage policies on weights and lengths here. 

I do not know about TSA - if in doubt, check it in as baggage.

https://www.southwest.com/html/customer-service/baggage/index.html?clk=GFOOTER-CUSTOMER-BAGS