Good answer Spit5, but I have to add something.
The PZL P-23 was produced as two variants.The first one which was assembled by PZL at the new factory called PZL WP-1 at Okecie-Paluch ,Warsaw at the end of 1935.It was the P-23A mark with Pegasus II M2 engine.The maximal ceiling for the Karas was of 5800m.Unfortunately problems with these M2 engines caused the limit to the P-23A ceiling which was exactly 3000m.The version of P-23A was using for quite short period of time and then in 1936 was replaced by P-23B powered by Pegasus VIIIA engine.Its maximal ceiling was 7300m.Lately the P-23As were used by airschools ( mostly Deblin).