The conical rubber gaiter (90 mm tall A) it will fit into the Bulkhead without a need to screw it in place. If you have a hole of 70 - 75 mm in a bulkhead the cable gland will hold its self in place, you can see in the images where the vernier calipers are placed on the gland there is a tight channel there designed to fix it in place in a 70 - 75 mm hole.
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