ST850 Transducers

The ST850 is the replacement for the ST650. It uses two knurled screw-down caps, one for the valve sleeve and one for the insert. It does not use a clevis pin like the ST650 did.

The ST850 uses the same non-valve P17/B17 housings as the ST650. The valve sleeve goes into the housing first and is retained by the larger cap, and the insert is then slid in and retained by the smaller cap.

This transducer can also be used as a replacement for the older ST100/ST550.

P17 Housing for ST850

ST850 with Valve Sleeve installed

ST850 with Insert installed

ST850 Valve Sleeve

ST850 Insert

ST850 Blanking Plug 33-522-01

Speed/Temp Insert Dimensions

Blanking Plug Dimensions

Available Parts

Part Part # Description
33-100 Bronze Housing B17
33-417 Plastic Housing P17
33-522-01 Blanking plug for ST850.
33-536-01 Paddlewheel kit.
(Part # depends on fishfinder brand) Insert for ST850.