2.1.4 Measuring In order to find the appropriate size for a male external catheter, the circumference of the penis needs to be measured. The penis should be measured at the shaft where its diameter is largest in order to assess the correct size (42). For measuring, the patient should be seated on the edge of a bed or chair with the legs slightly spread. In this free position both scrotum and penis are in their natural anatomic orientation and can best be measured. The actual male external catheter size of the penis may be hard to determine if it ranges between two sizes. Should this situation occur, the smaller size of the two should be selected. Male external catheter materials are sufficiently flexible and allow the penis a snug but not tight fit. Choosing the larger of two sizes might result in urinary leakage. Many manufacturers and suppliers of male external catheters offer sizing guides (for example cardboard molds or patterns), to help determine the size that will ensure safe and comfortable wear (33,35). It is important to note that manufacture sizes may vary, and sizing guides provided by one manufacturer should not be used for another.

Answered on Nov 5, 2012 9:59:02 AM by Dee  from RI

Try one of each to see what works better

Answered on Dec 23, 2012 2:49:17 PM by NYC  from Ca

The sizes are in mm's. Ask your father in law for a best guess then purchase three or four in that size and both smaller and larger.

Answered on Jan 6, 2013 6:18:16 PM by 5thtry  from Brandon