A 40 dollar Casio MTP-V005. Needed a wrist watch for work but also need to stack so I wanted an affordable one that checks all the marks. Does nothing but tell the time. It is a simple and beautiful design and it’s become one of my favorite items. 
Discussion
Looks stunning!!
If you like watches you should also check out the Casio Marilyn (MDV106-1A). Great diver for the money. You can usually catch them on sale for about $40 too.