both mk4's and mk6's are tricky to set when you first get them, as stated, have patience and try going that little bit further each day with them, both traps have the safety catch, once thats in place they are as safe as houses, put your thumb on the brass trigger, push downwards, this will open the trap a little more, with another finger, although sometimes they come up on there own, the pressure plate can be put into the trigger, all this is done while the safety catch is still on, if your having no luck today, walk away, try again tomorrow, it'll will come to you, dont give up so easy
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