The lever batten tips used in Wills Wing gliders are manufactured by Airborne Australia.  Airborne has posted a service advisory regarding the lever tips:  http://www.airborne.com.au/images/aw_directives/SB-019.pdf

The advisory addresses adjustment, maintenance and inspection issues with regard to the lever tips.  There have been incidents recently in which lever tips opening in flight have compromised the pilot’s control of the glider. Wills Wing has reviewed the contents of the advisory, and we concur with Airborne’s recommendations.  We encourage those pilots flying Wills Wing gliders equipped with lever tips to read the advisory.