Don't apply too much pressure to getting it off. You can really damage the eye that way.

If it doesn't come off easily, wait until the next shed cycle and really up the humidity...ie let him/her run through some warm, wet towels for a little while. That should help.
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Travis Rose
Lazy S Snake Ranch
3.7 Kenyan sand boas (various morphs)
1.2 Indian sand boas
0.3 Dogs
0.1 Cat
X.X Fish
0.1 Very understanding wife
2.0 Future Snake Lovers