The 3506-SC assembly contains a stud and coil spring captive in a steel cup. Flaring the end of the cup neck into a countersunk panel hole installs the assembly. When locked on the rigid wire in the receptacle, the spring is compressed and exerts a clamping force on the fastened parts.

P/N	Panel Tickness	Cup Diameter
3506-SC37A-Z3CT (PFSC3.5-37A)	.050-.059 in	.070
3506-SC38A-Z3CT (PFSC3.5-38A)	.060-.069 in	.080
3506-SC39A-Z3CT (PFSC3.5-39A)	.070-.079 in	.090
3506-SC40A-Z3CT (PFSC3.5-40A)	.080-.089 in	.100
3506-SC41A-Z3CT (PFSC3.5-41A)	.090-.099 in	.110
3506-SC42A-Z3CT (PFSC3.5-42A)	.100-.109 in	.120
3506-SC43A-Z3CT (PFSC3.5-43A)	.110-.119 in	.130
3506-SC44A-Z3CT (PFSC3.5-44A)	.120-.129 in	.140`

The basic DZUS finish, as called out by the tabulatee part numbers, is cadmium plate per QQ-Pp416, Type I, Class 2. Other standard finishes are available.
Other Available Finishes
BOC	Black Oxide over Copper sealer: clear acrylic dip
EEBT	Black Epoxy .0006 min. thickness with black epoxy enamel .0003 min. thickness Black Epoxy enamel color no. 37038. Applied over zinc plate per ASTM-B-633, Type III, SC2 Trivalent clear chromate with NO sealer.
Z3BT	Zinc Trivalent black .0003 thick. Trivalent chromate black dye with sealer.
Z3CT	Zinc Trivalent clear .0003 thick. Trivalent chromate clear with sealer.