What is Testosterone Enanthate 300 (Astera Labs)?
Astera Labs testosterone enanthate at 300mg/ml, in a 10ml multidose vial. The same ester everyone runs, in the format that means one item for the whole cycle instead of ten.
Also sold as Test-E, Androtardyl or testosterone enantate.
The enanthate ester is large, which slows the release. One injection keeps levels up for the best part of a week, so this is the ester you run when you want a stable base without thinking about it daily. At 300mg/ml it is more concentrated than the standard 250, which means less oil going in per dose.
Testosterone Enanthate 300 benefits
- 300mg/ml, so a 500mg week is under two millilitres of oil rather than two full ampoules
- One or two injections a week covers it, unlike the short esters
- One vial for the cycle instead of ten ampoules to open and dispose of
- The standard base for a first cycle, where testosterone alone is the right call
- Suspended in Miglyol 812, thinner than the oils most competitors use
Testosterone Enanthate 300 dosage
- Beginner
- 300 to 500mg per week
- Intermediate
- 500 to 750mg per week alone, around 500mg when stacked
- Advanced
- 750 to 1000mg per week, run alone rather than stacked
- TRT base
- 100 to 250mg per week
- Frequency
- Once weekly minimum, twice is better
- Half-life
- 7 to 10 days
At 300mg/ml the arithmetic is less round than at 250. 500mg a week is 1.67ml, so most people draw 0.85ml twice weekly rather than trying to hit an exact figure once.
There is no reason to push past the beginner range on a first cycle. The higher figures apply when testosterone is doing all the work alone.
Package content
- Vial
- 10ml sterile multidose
- Strength
- 300mg/ml
- Testosterone per vial
- 3000mg
- Carrier
- Miglyol 812
- Brand
- Astera Labs
At 500mg a week one vial covers six weeks.
Store below 30°C. Protect from light. Do not freeze. Keep out of reach of children.
Who is Testosterone Enanthate 300 for?
Anyone running a testosterone base who would rather manage one vial than ten ampoules, and who wants the higher concentration so there is less oil going into the muscle each time.
If you would rather each dose stayed sealed and sterile until the moment you use it, TESTOMED E 250 is the same compound as 10 single-use ampoules at 250mg/ml.
Before you run it. This replaces your own testosterone production for the cycle and for some time after, so
post-cycle therapy is part of the plan, not an optional extra. Testosterone aromatises, which is what the
estrogen management guide covers, and
bloodwork is how you know where you stand. Not for anyone under 18, and not for women who are pregnant or breastfeeding.
How to use Testosterone Enanthate 300
Intramuscular injection, once or twice weekly. Wipe the vial stopper with alcohol before every draw, and use a fresh needle to draw and another to inject. Rotate between glutes, quads and delts. The injection technique guide covers the technique.
Frequently asked questions
Vial or ampoules, which should I buy?
It is a practical choice, not a quality one. Ampoules are sealed single doses, sterile until the moment you snap one open, with nothing to contaminate. A vial is one item for the whole cycle, less packaging, and lets you draw any volume rather than a fixed 1ml.
The trade-off with a vial is that the rubber stopper gets entered ten or more times. Wiping it with alcohol every time is what keeps that a non-issue.
How long does an opened vial stay good?
An oil-based multidose vial is stable for the length of a normal cycle provided it is kept clean, out of light and below 30°C. The oil itself is not what spoils, contamination from repeated entry is.
Fresh needle every draw, alcohol on the stopper every time, and never return anything to the vial. Cloudiness, particles or a change in colour mean it goes in the bin.
How often should I inject testosterone enanthate?
Once a week is the minimum and it works. Twice a week, three or four days apart, is better: the same total dose produces a flatter curve, which usually means fewer estrogen swings.
Less often than weekly is where it falls apart. The half-life is seven to ten days, so stretching past that means levels are dropping before the next shot.
Is 300mg/ml better than 250mg/ml?
Not stronger, just more concentrated. The same 500mg week is 1.67ml at 300 versus 2ml at 250. Less oil per injection means marginally less discomfort and less volume to disperse.
Against that, the numbers are less convenient. At 250mg/ml a 250mg dose is exactly 1ml. At 300 you are measuring fractions.
Do I need PCT after testosterone enanthate?
Yes. Exogenous testosterone shuts down your own production for the duration and for some time after, and that is true at any dose worth running.
Because the ester is long, post-cycle therapy cannot start until it has cleared, which is roughly two weeks after the final injection. Starting earlier wastes the protocol.
