Ceramic Aquarium Shrimp Shelter - Vase 2  Part # ST150
 
Size Approx 8 cm D x 6 cm W x 7 cm H @ highest point / 2.5" D x  3" W x  2.75" H @ highest point
1  - larger entrance hole @ 3.175 cm x 3.175 cm  /  1.25" x  1.25"  
1  - smaller exit hole  @ 1 inch each   /  2.54 cm x 2.54 cm
Provides refuge and protection from predators
Can provide substrate for fine algae or bio-film
Seclusion for molting / female with eggs