These were the standard wood screw of choice used for decades until the advent of parallel shank screws, phillips drive heads and zinc plating. None of these enhancements are acceptable if you are engaged in restoration of work pieces which demand this period style. These screws have a tapered plain section under the head and use the 82 degree countersunk head angle still the standard today.
See table below for gauge code & dimensions. Note: We can supply around 30 variants of this pattern of screw. Please email for quotes for sizes & gauges not listed.
WHAT DOES GAUGE MEAN? - For decades wood screw gauges have been described using a wire gauge measure (usually BSW - British Standard Wire Gauge or AWG - American Wire Gauge) which bear no relationship to metric measurments. This means for example a 6 Gauge screw is not a 6mm screw. Machine screws on the other hand are more logical - a 6mm machine screw or bolt will be nominally 6mm diameter.)
Screw Gauge Nomenclature