Large. 1000 Ml 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