Like other reviewer, my hammer wetsuit constantly came undone at the neck and filled up with water. Sent off to O,Neill for repairs and they added an extra velcro tab and fastener across the zip. Fixed the coming undone, but it still fills up with water somehow - bought the size recommended to me - a size smaller than I would have bought.
I agree - this is the worst wet suit I have ever owned. Have heard of others who have had the same experience - one person was able to get a refund and buy a different brand.
Clearly poor design.

this is the most rubbish wetsuit i have used in 25 years of surfing, another bloke that surfs in my area has the same issues with the same wetsuit...the zipper comes down constantly when i duckdive and the wetsuit fills up with water...design fault, upon close inspection, the collar system , they claim to be the best thing since sliced bread , is useless , it does not secure the zipper at all....i tried to find a way to contact them, no email address, wrote a letter , no reply....i will never go near oneill wetsuits again...

The stretch in the O'Neill Hammer Wet Suit is amazing, for surfing it's awesome. I've been using mine for kayaking, had no soreness from it rubbing as it's very versatile!! A must have :-)