Lil' Hookey is a handy little tool to quickly and easily lock serger seams.
Here's how :
Snip seam tails at about 2 1/2"
Slip the Hookey blade into the serger seam 1/2" or more from seam end
Hook the thread tails near ends
Pull thread tails into the seam with hook slightly rotated toward fabric
Unhook secured thread tails and clip
Made in the USA
"" is currently out of stock but you can back-order the product.