The best connection to make between main line and a trace with a lure or hooks is a combination of a good quality swivel and a crosslock link.
I normally buy some swivels, about size 8 and buy the crosslocks separately. Recently I've had trouble finding crosslocks in shops. This gadget from Fox is similar in design and is strong enough to handle pike.
Fox International - Products - Safe-Lok Link Swivels
Avoid those safety pin type swivels which are sometimes attached to cheap swimfeeders. They aren't very strong.
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This link shows you various types of crosslocks and accompanying swivels. Can't vouch for the reliability of the brand, but the pictures show you how the crosslock is designed.
crosslock swivel | eBay
Finally, this type of safelink is acceptable for general coarse fishing, but not for pike, as it can open up under tension.
http://www.drennantackle.com/productDetail.php?category=48
Hope you have success lure fishing - it's a good time of the year for it.