The explaination of Zipperhead that was given to me during my time with Lord Strathcona's Horse (RC) at CFB Calgary was that in the old Cheiftans that we had during Korea had a flange over the vision blocks for the driver, gunner and commander that came nearly in contact with the crewman's forehead. During rough driving everyone would get bounced around and if one was trying to drive or observe through the vision block during the jostling it was very common to get a nasty gash on the forehead when this flange was rammed into the head of the crewman. The distinctive stitch pattern that this left on the forehead and that it was very visible gave rise to the nickname "Zipperheads" and the joke among Picklies (PPCLI) of "What do you get when you toss a grenade into a Chieftan? Zip-Dip."—This unsigned comment was added by 184.108.40.206 (talk).