Selecting a perfectly sized cock cage is an art. The ideal cage for you will be tight but not painful, constricting and humiliating but not to the point of physical discomfort, and be able to consistently prevent erection without permanently cutting off blood flow to the penis.
A properly fitted cage, as long as it is kept clean and regularly inspected, can be safely worn round-the-clock without any damage to the penis occurring. It will prevent all typical functions - save for urination - while the cock is enclosed, but ejaculation and even erection will still be possible during rare breaks when your Mistress allows your equipment to be freed.
Like Cinderella when the prince placed the glass highheel on her foot, or Goldilocks snuggling into Baby Bear's bed, slipping your cock into that properly fitted cage will feel "just right". In order to truly find the right cage, there are a few steps I recommend that you take first.
This handy-dandy guide will walk you through the process of measuring your cock and sizing your cage from the safety and comfort of your own home. No special techniques or fancy tools required!
A perfectly sized cock ring will fit snugly behind your testicles but will continue to allow blood to flow to the penis. It should not pinch or leave your equipment feeling numb or uncomfortable.
Because the penis is round and plump in shape, it is quite difficult to measure the diameter of yours on its own. Therefore, I recommend measuring the circumference - the full distance around your cock - and then performing a simple calculation in order to determine the diameter from there.
To obtain an accurate measurement of your cock's circumference, I recommend first taking a hot bath or shower. This will leave your cock flaccid but encourage the active flow of blood so that your final result will account for the slight swelling of the equipment as blood passes through. For best results, take your measurement immediately upon getting out of the shower or bath, before your body has had any time to cool down.
You can measure yourself using a number of common household objects. A measuring tape is made from yielding cloth which is specifically designed to measure round or irregularly shaped objects.
This can be easily wrapped around the cock just behind the testicles. If you do not own a measuring tape, you can instead wrap a length of string or ribbon around your cock, then straighten it out and record its length using a ruler.
Once you've got your circumference measurement, simply divide it by pi (approximately 3.14) to obtain the diameter. Below are a few examples of such calculations using popular cock ring sizes:
Circumference behind testicles of 157mm (6.1 inches) ÷ 3.14 = cock ring diameter of 50mm (1.96 inches)
Circumference behind testicles of 141mm (5.5 inches) ÷ 3.14 = cock ring diameter of 45mm (1.77 inches)
Circumference behind testicles of 125mm (4.9 inches) ÷ 3.14 = cock ring diameter of 40mm (1.57 inches)
Taking measurements for the long "tube" portion of your new cock cage is a significantly simpler process. You can use a straight ruler to measure the length of your equipment from base to tip.
As with the ring measurement, I recommend doing this right after a hot bath or shower, so that the penis is completely flaccid but there is some active blood flow to the area.
Stand up tall with your back straight. Place the edge of the ruler against the base of your penis and lay it flat on the top of your penis. Then, in order to obtain the most accurate measurement, press the ruler firmly against your pubic bone, which prevents any belly fat from getting in the way and messing up your measurement.
When choosing a cage, do not look for the tube which most closely matches your equipment in length. Instead, subtract between 1/4 inch and 1/2 inch (6 and 13 mm) from your measurement. For example:
Flaccid penis length of 4 inches = 3.5 or 3.75 inch cage
Flaccid penis length of 3 inches = 2.5 or 2.75 inch cage
Flaccid penis length of 2 inches = 1.5 or 1.75 inch cage
Flaccid penis length of less than 2 inches = 1 or 1.25 inch cage
The ideal cock cage tube will fit your penis tightly but not constrict it to the point that it cannot release urine. Ideally, your urethral slit will lie against the opening at the end of the tube. The width of the cage will be narrow and completely prevent you from achieving erection, no matter how aroused you may become.