I purchased theScopetronix thread on Class A Solar Filter for the ETX60/70 (Item STSF70) from Astro Optical Supplies in Melbourne.
Not a normal stock item, I did have to wait around 2 1/2 months for it to be ordered in but that's the way it goes I suppose.
The Class A filter comes with a warranty for the life of the product - for the original owner. This thread on version gives a safe and snug fit for the ETX70. Mention is made that pin holes are rare in this particular brand of filter but any which occur can be masked with a felt tipped pen. They recommend a maximum of 20 touch-ups per aperture inch with no adverse effects on performance or safety.
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