The powerful Citizen CL-S631 provides users with unparalleled features in the desktop thermal printer class. With crisp 300 dpi printing for images or fine text and an unprecedented 360-meter ribbon for greater productivity and reduced downtime the CL-S631 is a high-performance printer built for the desktop environment. Citizen's unique metal Hi-Lift™ mechanism allows easy access for loading of media and/or ribbons and the adjustable media sensor can handle a wide variety of label configurations including standard and pediatric medical wristbands. The powerful on-board 32 Bit RISC processor delivers exceptional throughput and fast first label out. The CL-S631 comes standard with internal serial and USB interfaces. Optional Ethernet, Wifi, and Parallel interfaces are also available.
| Model | CL-S631 | 
| Printing method | Thermal transfer & Direct thermal | 
| Printing width | 104 mm (4.1 inches) max. | 
| Minimum print length | 6.35 mm (0.25 inches) | 
| Maximum print length | 812 mm (32 inches) | 
| Media width | 19.5 - 118 mm (0.77 - 4.65 inches) | 
| Printing speed | Thermal transfer mode: 101.6 mm (4 inches) per second Direct thermal mode: 6 inches per second  | 
        
| Resolution | 300 dpi | 
| Barcode type | Code3 of 9, UPC-A, UPC-E, Interleaved2 of 5, Code128, EAN-13, EAN-8, HIBC, CODABAR(NW-7), Plessey, Int2 of 5, CASE CODE, Code93, ZIP, UPC2DIG ADD, UPC5DIG ADD, UCC/EAN128(for K-MART), RandomWeight, Telepen, FIM, UPS MaxiCode, PDF417, Data Matrix, and QR code | 
| Paper | Thickness: 0.0635 - 0.254 mm (0.0025 - 0.01 inches) Outer diameter: 127 mm (5 inches)ø MAX Paper core diameter: 25.4 - 76 mm (1 - 3 inches)  | 
        
| Ribbon | Length: 360 m Outer diameter: 74 mm (2.9 inches) Core diameter: 25.4 mm (1 inch)  | 
        
| Interface | Standard interface: RS-232C and USB (USB1.1) Optional: LAN and Parallel (IEEE1284-ECP /Centronics compatible)  | 
        
| Fonts | 9 fixed pitch, 2 proportional font | 
| Buffer size | 512 KB | 
| Options | Auto-cutter, peeler, LAN interface board, and Parallel interface board | 
| Power source | AC100-120, 200-240V 50 / 60Hz | 
| Weight (approx.) | 4.9 kg | 
| Outer dimensions (W × D × H)  | 
            231 x 289 x 263 mm (9.1 x 11.4 x 10.4 inches) | 
| Reliability | MCBF 1000 km, Printhead 50 km | 
| Safety standards | UL, C-UL, FCC: class A, CCC, CE Marking |