Visual Spark plug Cap

[Bogan Thunder]

WTF...does it glow green when started.

 

[Rep732]

What it appears to be is an inline spark plug tester, sounds like more to go wrong.

 

[Dunc2504]

I usually rely on the fact it is running to tell me it has a spark

 

[smokinwheel]

What it appears to be is an inline spark plug tester, sounds like more to go wrong.

I usually rely on the fact it is running to tell me it has a spark

Yes to both of these.
Why add another gizz-mo to a proven system and if it is making noise and blowing smoke you stand a real good chance it has spark , and guess what it is also getting fuel if it makes noise.

 

[Bogan Thunder]

I usually rely on the fact it is running to tell me it has a spark

it does look bizarre..it's just a hobby product that's not needed i would rather just buy a spare plug.