Samsung EVO SSD as replacement for laptop: skinny or normal?

[NickIsAngry]

I'm about to purchase an Asus Q504UA 2in1 laptop. The HDD is sub-par so I'll replace it with an SSD.

My question is do I purchase this:
Samsung 850 EVO - 250GB - M.2 SATA III Internal SSD (MZ-N5E250BW) https://www.amazon.com/dp/B00TGIVZTW/ref=cm_sw_r_cp_apa_ZMQ0ybT9FFZFN

Or do I buy this:
Samsung 850 EVO 250GB 2.5-Inch SATA III Internal SSD (MZ-75E250B/AM) https://www.amazon.com/dp/B00OAJ412U/ref=cm_sw_r_cp_apa_5NQ0yb5J30YS1

I am unsure of the dimensions so any help is appreciated.

 

[koreanoverlord]

I do not believe your laptop supports an M.2 drive. So go with the bottom one.