| RK0 | RK#0 / 1.75 in. Ring with Knob pessary | |
| RK1 | RK#1 / 2.00 in. Ring with Knob pessary | |
| RK2 | RK#2 / 2.25 in. Ring with Knob pessary | |
| RK3 | RK#3 / 2.50 in. Ring with Knob pessary | |
| RK4 | RK#4 / 2.75 in. Ring with Knob pessary | |
| RK5 | RK#5 / 3.00 in. Ring with Knob pessary | |
| RK6 | RK#6 / 3.25 in. Ring with Knob pessary | |
| RK7 | RK#7 / 3.50 in. Ring with Knob pessary | |
| RKs0 | RKs#0 / 1.75 in. Ring with Knob pessary with support | |
| RKs1 | RKs#1 / 2.00 in. Ring with Knob pessary with support | |