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index 8403dca..90ab65b 100644
--- a/README.md
+++ b/README.md
@@ -2,6 +2,9 @@
 
 This repository contains the best trained models for the
 [Tesseract Open Source OCR Engine](https://github.com/tesseract-ocr/tesseract).
+
+These models only work with the LSTM OCR engine of Tesseract 4.
+
 See the [Tesseract wiki](https://github.com/tesseract-ocr/tesseract/wiki/Data-Files)
 for additional information.