1. Sterile, disposable, ready to use
2. Shaft curved properly (uterine sound shaped) for use in anteverted or retroverted uteri
3. Snap-on cervical stop custom set for every patient 
4. Snap-on cervical stop V-shaped design for easy view of external cervical os
5. Patient ambulatory once instrument properly inserted 
6. Durable no-crack luer fitting on flexible collar for convenient injection 
7. No spring or weights added