Tecnoseal X8 Shaft Anode - Zinc - 1-3/4" Shaft Diameter [X8] Marine Plumbing & Ventilation | Fittings it offers very good performance

it offers very good performance as it is specifically tuned to 162MHz (AIS frequency)

Use this Shadow Drive attachment to automatically disengage the autopilot if the helm is turned

Features built-in backflow preventer

the iTC5 provides all

It also reduces battery drain

Tecnoseal X8 Shaft Anode - Zinc - 1-3/4" Shaft Diameter [X8] Marine Plumbing & Ventilation | Fittings it offers very good performanceShaft Anode Material: Zinc Outer Diameter: 3. 20" Inner Diameter: 1. 75" Height: 3. 06" Weight: 2. 56lbs Holes: 4 Specifications: Material: Zinc Box Dimensions: 3"H x 3"W x 3"L WT: 2. 7 lbs UPC: 8059617812454 Quick Guide (pdf) Owner's Manual (pdf) Brochure (pdf)