For the micro ring,we have 3 size there: 4.5 x 3.0 x 3.0 mm,4.5 is diameter of outside,and 3.0 is inner diameter,3.0 is length; 4.0 x 2.7 x 2.7 mm,4.0 is diameter of outside,and 2.7 is inner diameter,2.7 is length; 3.5 x 2.0 x 2.5 mm ,3.5 is diameter of outside,and 2.0 is inner diameter,2.5 is length; popular size is 4.0mm package: 1000pcs/bottle Currency: Unit Price: Quantity: package: 1000pcs/bottle Delivery: for customer's request