100 ml Glass Water Bottle with stopper and sipper tube. Graduted by one (1) ml. The diameter for the 100ml bottle is 1 1/16" with a 6.5 stopper. Ball point tube provides cleaner water by significantly reducing backflow of bacteria into the bottle. Extends bottle use between refills, allows longer cage use between bedding changes and reduces watering costs. Ball Point Tubes have 2 balls and a 5/16" opening. Open drinking tubes (no ball) have a precision curved tip and stainless steel, thin wall construction. Standard 5/16" diameter with 1/8" end opening.