Carabiner with spring loaded secured lock

A carabiner with a spring loaded locking mechanism.

My first 2 versions of a locking carabiner was with a screw, but it took too long to open and close. As these plastic carabiners are not ment to handle large loads like of a person, the locking mechanism dont need to be that strong. This isnt ment for heavy loads, but can probably handle 100kg.

Hardware: (you need this to be able to use it)
3x M3x8-10mm (any head will work but button or socket is preferred)

@MauriceHauff_1314206 suggested 8mm works best and I agree, but 10mm can work too if you dont mind the screws poking out on the backside.


A Ø7mm x 19mm spring like in the photos. Mine was from a set I bought many years ago from banggood and I cant find the order to see what dimension it was. I have attached photos where its measured with a caliper.

(Optional screw, without it, the slider lock may fall off when the carabiner is unlocked, the screw goes on the top of the “hinge”-part after the spring and “slider”-part are inserted)
1x M3x5mm (button head)

Update 20.06.2024:
Made an improvment on the slider so it dont jam on the main body when opening/closing
(Check out the 7th photo in “photos”)

I hope someone out there have the equipment to test it to see what it actually can lift before it breaks.