A new system from Woodhead Industries Inc., Deerfield, Ill. (woodhead.com), the Ultra-Lock Connector System, uses radial seals on cables and distribution boxes. They provide watertight, IP68 connections that protect against moisture and chemicals. Connectors lock in place by pushing down, forming a radial seal with the O-ring. The cables click into place, confirming a good connection. Threaded connectors often use compression seals, but if they're too loose, the O-ring does not fully seat, moisture can enter, and the electrical connections can be intermittent. If the connector is too tight, the O-ring can deform and fail. Once in place, cables are secure enough to resist flexing, vibrations, and mechanical shocks. To remove them, technicians merely pull up on the connector. Three and fourpole cables are rated for 250 V, while five-pole versions handle up to 60 V. The cables can handle up to 4 A and operate at 25 to 90°C.