GM811 series have GM811-S and GM811-L model.
The only difference between GM811-S and GM811-L is the lens.
GM811-S lens reading distance is 5-30cm.
GM811-L lens reading distance is 7-50cm.

GM811 series bar code reader module is a high performance scanner, can read 1D bar code easily and read 2D bar code with high speed. It also wins high scan speed for linear code, even for bar code on paper or screen.
GM811 series bar code reader module is an advanced bar code decoding algorithm which developed on image recognition algorithm, can easily and accurately read bar code, simplify secondary development.

GM811 mainly parameter:
·Decoding Ability:
1D: EAN-13, EAN-8, UPC-A, UPC-EISSN, ISBN, CodaBar,Code 128,Code93, ITF-14, ITF-6, Interleaved 2 of 5,Industrial2of5,Matrix2of5, Code 39,Code11, MSI-Plessey,GS1 Composite, GS1-Databar (RSS)
2D: QRCode, DataMatrix, PDF417
·Operating Voltage: DC 5V
·Operating Current: 70mA
·Interface: TTL-232,USB
·Dimension: 50*50 mm
·Accuracy of reading: 10mil

More details pls click here:
http://en.hzgrow.com/product/197.html

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