TetherSpout Device is one piece with ball, one piece for normal, which desiged for someone who has chastity requirement but non-piercing.It can be used separately or used with cage. Want to know more about it,visit this link. http://tetheredchastity.blogspot.com Here are 3 existing combinations of TetherSpout. E1:as below length 28mm barrel diameter 6mm flange diameter 8mm ball 12mm 4 retaining rings' diameters 10mm and 11mm,12mm,13mm E2:as below length 28mm barrel diameter 7mm flange diameter 9mm ball 14mm 4 retaining rings' diameters 11mm and 12mm,13mm,14mm E3:as below length 28mm barrel diameter 8mm flange diameter 10mm ball 16mm 4 retaining rings' diameters 12mm and 13mm,14mm,15mm Tip: the screw is to "bite" the solid wall, not screw into the tether hole.No need to twist screw wrench with big force to bit the wall, when screw in the screw.You can stop when you feel the twist become a little tight. if you want the normal without ball, pls check: https://www.bonanza.com/listings/Titanium-TetherSpout-For-Nom-Piercing-Chastity/1658461122