I don't recall having such a strong need for these when my kids were little but boy I use them frequently on projects for my grand kids. I have used them for connecting safety chains on the zip line. They are great for securing bars to trapezes or swings to ceiling joists. They also make securing chests or doors while eliminating the need for a lock. They are surprisingly expensive at the local hardware store or even the big box stores. It isn't unusual to spend $2.50 for one. Therefore the price on Amazon is a terrific bargain. Take note these are not heavy duty type lock links. I have used two in place of one if there is a need for safety. However for general use, even if I use two instead of one, the price still makes it a bargain.
Price: $14.88 & FREE Shipping on orders over $35 at Amazon
Details from Amazon
Weather-Resistant Nickel-Plated Finish
Lock Nut for Secure Connection
Quick Connection Point for Chain, Rope or Cable
Comes with a Plastic Organizer Box for Storage
Purchased, not free to review.
If reviewing a product, it may have been received free of charge. That will NEVER have a bearing on my recommendations.