A cover?
Do you mean:
1. you've removed, fractured or otherwise compromised the waterproof nature of the plastic housing the
electronics and electro-mechanics?
or
2. you want a cover in which to stow your
Simrad tillerpilot when it's not in use?
or
3. you want a cover to disguise, camouflage, or protect from UV your tillerpilot when it's in use?
Al (who has an
Autohelm tillerpilot and been running it for years sans cover)