This is a transparent, ribbed hot water bottle, likely made from PVC or rubber. 

Used for warmth and pain relief from muscle aches, backaches, or menstrual cramps. 

Can be used for both hot and cold therapy. 

Features a wide mouth for easy filling and a screw-on cap to prevent leaks. 

Capacity: 250ml/ Size: 20x15cm

Disclaimer: Use caution when filling; do not use boiling water.