Lexmark 4I3 - Manual (Page 281)

Cut Sheet Forms — F3
Dimensions
Forms Maximum Minimum
Width 381 mm (15 in.) 76.2 mm (3 in.)
Length 355.6 mm (14 in.) 177.8 mm (7 in.)
Thickness
The thickness of all forms should be a minimum of 0.08 mm (0.003
in.) and a maximum of 0.25 mm (0.010 in.).
Acceptable print quality will be provided when using single-part
forms. If you use forms having more than one part, you should test
them for forms handling, print registration, and print quality.
Weight
Minimum weight for single-part forms is 56 g/m (15 lb). Maximum
weight for single-part forms is 150 g/m (40 lb). The best range is
75 to 90 g/m (20 to 24 lb). Paper weights outside the functional
range should be tested by the user.
Performance Considerations
When using the F3 device, you can use a width of up to 381 mm (15
in.). However, for optimum feeding and print registration, a
maximum width of 330 mm (13 in.) is recommended. For optimum
performance, printing should be restricted to 127 mm (0.5 in.) from
all edges of the form.
Forms are available from IBM or any forms supplier.
Appendix C. Forms Information C-3