Medium. 600 Ml With Valve Bx/12 * Durable Yet Soft Comfortable Vinyl Construction Provides Optimum Performance And Comfort * Valve Provides Simple Non-drip Closure * Anti Reflux Valve Prevents Urine Backflow * Easy To Use Straps Provide Secure Attachment To Legs * Sterile Fluid Path * With Twist Valve * * Attach Directly To The Catheter; No Tubing Necessary * Not Reusable