You can find this Beach Bag on Etsy.
 
Large Beach Bag features include:
	
Key fob clasp
	
Fully lined with matching fabric
	
Patch pocket in complimentary plain blue
	
Elasticated bottle holder
	
Reinforced fabric straps
	
Machine washable (at 40° or below) - hand washing is advised
 
Measurements (all measurements are approximate):
Height ~ 34cm (13.5")
Width at top ~ 51cm (20")
Width at bottom ~ 35cm (13.75")
Depth at bottom ~ 12cm (4.75")
Strap length ~ 65cm (25.5")
Pocket size ~ 19.5cm x 14.5cm (7.75" x 5.75")