I assume that you're talking about the brass locking clip and spring/knob? If so, remove the knurled knob from your replacement and place a small drop of blue Loctite on the threads, then re-secure the knob...this will keep the knob from backing off in the future.
I've had nothing but excellent service from Lee filters.
A few years ago I put a brand new proglass filter in a new filter holder and the filter dropped right through the holder onto the granite pier I was standing on (granite wins).
I wrote a letter to Lee filters and they asked me to send in the filter holder for testing. They determined the plastic retention clips/springs that hold the filters in place were at fault and they changed them out and replaced my proglass filter for free.
Great products from a great company. Seems they are currently struggling to keep up with demand though.
