STP1-11 vs ETA 2824-2 Cal. compared side by side. Will it measure up?

STP1-11 vs ETA 2824-2 Cal. compared side by side. Will it measure up?

For years ETA movements have been widely regarded as the movement of choice for many high quality (micro) watch brands, but their reign is coming to an end. ETA has been winding down international operations after its holding company, Swatch Group, decided it will no longer supply ETA movements to brands outside the Swatch Group.

This decision has paved the way for other Swiss movement manufacturers such as Sellita, Ronda and now STP to fill in the gap they leave behind, by supplying movements of matching or even better quality to micro brands such as pOrtahl. ETA’s patents have long run out, further closing the gap in quality between ETA movements and other manufacturers as they can all base their designs on the proven ETA Calibers, or even improve on them.

Let’s compare the STP1-11 to ETA’s widely popular ETA 2824-2 Cal. and see how it measures up.

We’ll keep it short and sweet!

STP1-11 vs ETA 2824-2

Power Reserve

The STP1-11’s design was inspired by the ETA 2824, however the STP Caliber uses a longer and thinner mainspring resulting in a boosted power reserve of 44 hours. That is 6 hours more than its ETA counterpart.


STP1-11 has an accuracy of -3s/day to +7s/day, resulting in a difference of max 10 seconds per day. On the wrist this would result in an on wrist performance of +/- 2 to 4 seconds as per research done by WatchGuy. This is significantly more accurate than the ETA 2824-2, depending on which grade of the 2824-2 Cal. we’re comparing with, as ETA’s 2824-2’s accuracy can vary between +/- 4 to +/- 30 seconds per day. The STP1-11 will in many cases beat ETA in accuracy.


The STP1-11 sports 26 jewels, which is one jewel more than its ETA counterpart which contains 25 jewels. This extra jewel is used to support the top of the barrel arbor, thus prolonging its longevity as the barrel bridge can easily wear out. On this front too STP’s 1-11 is an improvement on ETA’s 2824-2 Cal.

Quality & Finishing

The quality of a movement can often be derived from the finishing and the STP1-11 can compete with the best in its class. All movements by STP come with pearlage, a Glucydur balance wheel and Côte de Genève finishing on the rotor. The Côte de Genève decoration can not be found on the standard ETA 2428-2. Lastly, all markings on the STP1-11 are better executed than the ETA, as per WatchGuy’s findings following a microscopic comparison.


All in all the STP1-11 can be seen as an improvement on the watch industry’s beloved ETA 2824-2. It has all the things we love, appreciate and have gotten used to… But even more. Added longevity, better finishing, slightly better accuracy and a bigger power reserve.

What’s not to love?


Interested to see more comparisons of pOrtahl's STP1-11? Have look at these articles below.

Back to blog