Can’t be too long. Don’t know if a lazer is shorter or something but I’ve had to put the plate all the way onto ice and sometimes it would go through, sometime not, on Vermilion.
I should clarify that I’m not saying you need 20″ instead of a 12″ to get through anything. I probably needed a 1″ in this case and that’s the thickest ice I’ve ever seen. Longer one = less bending over or needing to kneel though when the ice is really thick and that’s why I’d want a longer one.
I’m also 6’5″ though so maybe a 20″ would be annoying for some people? For me I had to kneel a lot with the clam drill plate when the ice was really thick without an extension. I’m not real flexible and definitely can’t touch my toes standing up