PROEXL15K Sports Magnetic Bracelet 100% Waterproof and Fully Adjustable, 9 5 inch, Silicone

Q: can you buy additional straps tucks to replace stretched out ones?

It's one piece. Had mine 7mos now, hasn't stretched or worn. Only issue I've ever had is I sorta wear it upside down, where it snaps together is on top of my wrist as opposed to bottom, because it would occasionally come apart while I slept or brushing against my pants. Hope that helped.