A lot would depend upon the relationship you had with the sender. Yes your email is fine, but I would suggest replacing the word 'kind' with 'just a quick/gentle reminder [ what it is about here] Thanks in advance for an informal relationship or "Thank you" for a formal relationship. Emails go astray all the time it's ok to chase them up after there days max, after this time it is certain they have not responded. It is an email not a letter by post.

I usually say, "Hi, so and so. I am just emailing to follow up on my email below" That makes it sound like I am the one who was supposed to take action, rather than the recipient feeling like he or she forgot to respond(even though he or she did forget).

Hi there, It's preferable here in England that you don't send a reminder, as it may seem rude and impatient of you and the person you are sending the email to may be very busy. The only exception is that if you really need something and a deadline is approaching. Only then could you send a reminder mentioning the task you required and possibly the deadline you have to reinstate the urgency. Hope it helps (It's better to say "could I remind you of (task) which I need by (deadline)" Yusuf