Initially, barcodes represented data by varying the widths and spacings of parallel lines. The check involves rules that specify widths and spacings and other geometry patterns. This contrasts with variable-width fonts, where the letters and spacings have different widths. With these methods, layers can be produced with thicknesses of only a few atomic spacings. This method has been used to fabricate arrays of gold nanodots with precisely controlled spacings. The size of the echo is recorded for different spacings of the two applied pulses. The size of the echo is recorded for different spacings of the two pulses. Sometimes these spacings may be quite arbitrary. The result is energy level spacings that are approximately independent of offset charge. Current industrial planting spacings can range from 7 x 7 to 20 x 20 m. Bore spacings for all variants of the SBB are . The spacings of the basic elements in the scaffold are fairly standard. These were similar to A4 frames except for the wheel spacings at the front. Transit time effects are reduced by reduced spacings in the tube. WE/SS and Tyco/AMP 8P8C plugs have different spacings for the cable strain relief.