
We’ve all heard, “practice makes perfect” when it comes to self-improvement in life. However, how many times have you associated this with sexual skill?
Although you might now be smiling, thinking to yourself, “Well, I have,” you’d be surprised to know that most have not!
Here at Fleshjack, we developed the Stamina Training Unit (STU) Butt to boost your endurance in the bedroom with that special someone.
The STU Butt specializes in mimicking the intense, pleasurable sensations you encounter in intercourse, which, with regular training, may boost your sexual stamina and heighten your performance.
The Stamina Training Unit by Fleshlight, can not only help you improve your sexual stamina but boost the intensity and frequency of your orgasms. Not only can you experience more powerful climaxes through the use of Fleshjack’s STU but, after training, your partner may notice an increase in his as well.
As our #1 selling product worldwide, the STU Butt is popular for a very simple reason–there’s nothing else like it!
Continue reading to learn more about this amazing sleeve, its dimensions, and more.
Stamina Training Unit Butt: The Details
STU Butt: Measurements
The STU Butt sleeve (as you might have noticed) has an inviting tight anal entrance that leads to an insertable length of 8.5 inches (21.6 cm) and a snug canal diameter of 0.45 to 0.6 inches (12-15 mm).

The full case, with the sleeve nestled inside, measures at 10 inches (25cm) long and 4 inches (10cm) in diameter. This sized toy is small enough to be easily concealed at home but big enough for nearly any size man.
STU Butt: Sleeve

The sleeve’s small, tight anal opening leads to an interior that is made up of large, pillow-Esque, bumps that will push even the most experienced gay man to his limits.
As you thrust in and out, you’ll notice the dense bump texture gives an exceptionally intense stimulation to your penis. The bumps wrap neatly around your penis, massaging the shaft and head from all sides. Add to this a strong suction effect, and you’ll be testing your endurance with each and every use.
STU = Pleasure + Backdoor Training
It’s important to keep in mind that the Stamina Training Unit Butt was designed equally as both a pleasure toy AND training device to help men overcome premature ejaculation and performance anxiety.
Most men won’t last long on their first several tries, but that’s the idea! With consistent training, you should strive to gradually develop the ability to control your speed of ejaculation.
What’s Included With Your STU Butt?
Now that you’re ready to take your sexual endurance to the next level, here's what you can expect once your Fleshjack package arrives at your home.
- Exclusive gold case
- Patented SuperSkin sleeve
- Anal orifice
- Instructions for use and care
- FREE e-guide for increasing your stamina
No more “minute-man.”
No more disappointing your partner (or yourself).
It’s time to greatly improve your sexual endurance and confidence.