Marine Grade Electrical Wire Grommets - 5-Pack, 1/2". Flexible black vinyl provides instant abrasion resitance to wires passing through panel holes.. Features:. Flexible black vinyl. 5-Pack. 1/2". WARNING: This product can expose you to chemicals including di(2-ethylhexyl)phthalate (dehp) which is known to the State of California to cause cancer, birth defects or other reproductive harm. For more information go to P65Warnings.ca.gov.