The ornamental design for a four-way spider fitting for a filtersystem, as shown and described.
FIG. 1 is a perspective view of a four-way spider fitting for a filter
system, according to the present invention.
FIG. 2 is a top plan view of the four-way spider fitting for a filter
system.
FIG. 3 is a bottom plan view of the four-way spider fitting for a filter
system; and,
FIG. 4 is a front elevation view of the four-way spider fitting for a
filter system, the fitting having a symmetrical opposite rear elevation
appearance, and a similar appearance in side elevation view at a view
point 90° from that shown in FIG. 4.
The broken line showing of environment in the drawings is for illustrative
purposes only and forms no part of the claimed design.