We have discovered that a small percentage of the RSK Mk5 production sheaths do not secure the knife properly due to tolerance stack-up. If you are concerned that your knife is not retained properly in its sheath, an easy test is to lift a standard 12 oz. beverage can by the lanyard and see if the knife is retained (see images below or video at:
http://www.dougritter.com/video/RSK_Mk5_Sheath_Test.wmv ). A paper clip, as shown below, is an easy way to connect the lanyard to the can's pull ring.
Do NOT jerk the knife upward as that invalidates the test. If the knife slips out of the sheath when the can is simply lifted up gradually and smoothly, then CRKT will be happy to replace your sheath.
WARNING: Use caution when performing this test to avoid injury. Conduct this test on the floor so that if the knife does come unsheathed, it will not drop or bounce in an unsafe manner. Wear shoes and take appropriate precautions to protect yourself if the knife comes unsheathed.
If your sheath does not pass this test, please contact CRKT at the contacts below to receive a replacement sheath. CRKT is retooling the sheath to allow for the tolerance issue, so please allow 30-60 days for the sheathes to be redone. In the interim, some owners have found that heating the empty sheath with a heat gun or hair dryer and squeezing the opening for a tighter fit provides a temporary solution (use care not to burn yourself on the hot plastic when doing this). We apologize for any inconvenience.
CRKT Contacts:
Email: info@crkt.com
Phone Toll Free: 1-800-891-3100