Type S Slide on

Sentinel type

The Sentinel Type Anodes slide onto a steel rod and then screw into a brass plug.


Brass Plug Part Number NPT Size Internal Thread Use with Element Part Number Plug NPT Size Inside Diameter Outside Diameter
SP-250 1/4" 10 24 S-438 S-438 1/4" OR 3/8" .1875" .4375"
SP-375 3/8" 10 24 S-438 S-500 1/2" .1875" .500"
SP-500 1/2" 10 24 S-500 S-813 3/4" .1875" .8125"
SP-750 3/4" 10 24 S-813 S-1000 1" .1875" 1.000"
SP-1000 1" 10 24 S-1000 S-1500 1-1/2" .375" 1.500"

Stainless steel rods for sentinel anode
Part Number Rod Size Use With
SR-3 3/16" x 3" S-438 - S-500
SR-6 3/16" x 6" S-813 - S-1000