The swivel snap is way heavier than an aluminum biner... but not as heavy as a steel snap.
The ISC 2 and 3 action aluminum snaps without the swivel arent as heavy... I would think that the Twister (swivel) Snap on a 10mm cord would throw fine. The twister is considerably longer though than a standard steel snap, the ones without the swivel are comparable in length... Its about 7.5 inches to 5.5 inches... here is a video on the ISC snap...
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Like I said it takes a bit getting used to, engaging the front safety first. In use, you dont have to 'activate' the rear palm safety, when you pull the front lower one, your palm automatically pushes the palm safety in. So for all intents and purposes you are simply pulling the front bottom on and then opening the gate.