Getting advice on Jail Bird size adjustments

Alright, I’m considering picking up a Jail Bird, but it’s quite an expense, so some advice would be great. I’m currently running with a small Holy Trainer and the 45 ring. What bothers me is that washing while wearing it feels nearly impossible, plus I get this burning sensation under my scrotum, especially at night. I hope the Jail Bird fixes these issues, but getting the fit right is key. Drawing from my time with the small HT, here’s what I see regarding size:

• The 45 ring might be slightly loose for me, while the 40 feels too tight once the device is locked on (though it probably fits well without it).
• The tube length seems a bit long since I often get “turtleing” inside the cage.
• The tube diameter feels a little small because stuffing myself in there can be tricky. (If I switch to the Jail Bird, I want enough width so I don’t bulge out sideways…I find that look somewhat unappealing).
• The space between the ring and the device is likely too narrow since my scrotum usually sits “high and tight”. Given all this, here’s what I have in my cart for the Jail Bird: Ring Style Round Cage Length 1 1/2” Ring Size 1 5/8” Cage Diameter 1 5/8” Lock Options Security screw & keys Second Pin Medium Criss-Cross Pin Third Pin Medium Blunt Pin Cage/Ring Gap 1/2” Extra Cage Rings None Punishment pins Small Criss-Cross Pin Any input, especially from those who own a Jail Bird, would be much appreciated.

I haven't used HT devices myself, but I have plenty of experience with the Jailbird. Getting custom measurements spot-on initially can be a bit of a gamble (I’m currently using my third MM device). Here’s what MM told me: almost every measurement on an MM model is affordable to adjust later compared to buying a new unit entirely, except for the cage diameter. So, make sure you nail that first. Base rings can be stretched, gaps adjusted, and even cage length modified up or down easily. Go ahead with your best guess, but don’t stress too much about every single measurement as long as the cage diameter is correct.

My best advice is to order the sizing ring set from MM. Use the larger rings to find a comfortable size. They come in ⅛ inch steps, so it’s worth testing several out by wearing each for a few hours or even days until you find what feels right. The smaller rings are also useful for checking cage diameter.

I’ve ordered the sizing rings now, but do you have any advice regarding length? I’m still thinking about my SMALL Holy Trainer and how much turtling it has.

Yes, they offer many size adjustments at a low cost. However, if you aren’t in the USA, expect high shipping fees both ways and a transit time of weeks rather than days. That’s not MM's fault; just keep it in mind. For length sizing, measure under your shaft multiple times from where it meets the scrotum to the tip. As someone who is more "grower" than "shower," I used my finger as a ruler, marking where the end of my shaft hit against my fingertip when placed at the base. After checking around 20 times, the average length became clear, and then I just measured that spot on my finger with a tape measure. For cage diameter, use those rings to pick the one that slides over your relaxed shaft most easily. In my experience, the cage fits snugly in both width and height constantly, though it can feel slightly long on cold days! One quirk of the JailBird design is that its "gap" isn't always exactly ½" or ⅜". That number refers to the straight-line distance along the spine where the cage attaches between adjacent ring and cage faces. Since the ring and cage have different diameters, and depending on whether the ring is round or oval, the actual gap can vary from very close to nominal to significantly larger. This measures the surface-to-surface line directly across. On my unit with a ⅜" gap and an oval ring, the real gap stretches to nearly ⅝". This actually helps because it pushes the scrotum toward the wider area, reducing pinching. HOWEVER, I have had some painful partial escapes because my left testicle is smaller than my right (a common male trait), making this gap feel a bit too large for me. Because of that, I’d be careful about shrinking the gap based on another device's dimensions.

For cage length, measure yourself from the top side while totally flaccid. Take several readings over a few days. Then take your ring gap and add it to the base ring thickness (typically ¼ inch), subtracting that total from your measured length. Example: Flaccid length of 2.75 inches minus (.25 in + .25 inch gap) equals 2.25 inches. This should provide a good fit for length-wise issues. Since there is usually a difference between the base and cage ring diameters, I recommend choosing a smaller gap, like 0.25 inch. That way one of your nuts won't pop through. I wear a Jailbird myself and love it. It's very comfortable and easy to keep clean. Cage diameter: 1.25 inch Ring diameter: 1.75 inch (oval) Base ring/cage gap: 0.25 inch Cage length: 2.5 inch Security screw

Best of luck. After waiting a while, my Jail Bird arrived today. Before this, I wore an HT2 with a 40mm ring and short tube. That fit was almost perfect, just slightly too long. I can't recall the exact measurements for the JB (my mistress ordered it), but every dimension is one notch smaller than the HT2—except the cage length, which I believe is 1.5". I measured myself several times over multiple days and found that length was the trickiest to get right due to inconsistency. The JB fits quite tightly—but well enough. It’s hard to say if my sizing is perfect yet; time will tell. I don’t think you can avoid some bulging between the bars when aroused during normal daily wear, no matter what size you pick. Even a slight touch causes it, which Mistress enjoys. Quality-wise, it feels much better than the HT2. Hopefully, it solves all my previous issues with that device, provided it isn't too small.

Another question... About the screw lock. I assume the "key" is basically a specially fitted screwdriver? Is it a universal shape or do they vary?

I own three different MM devices and they all share the same key. It has an acute triangle shape and only fits into the screw head in one orientation.