Key decisions

Following on from my last post I had also decided that I might try some CW operating when I next use the portable gear. In the past I have worked SSB only but with my very limited antenna system I should get better results with CW. I have two keys here in the shack, both my paddle key and the straight key are too large and possibly too fragile to take along in my portable kit. I mentioned this fact in a conversation on 2 metres a few days ago and a local GW3 friend told me he had three keys that he would be interested in selling.
A few days later he called around with the keys, leaving them with me to try them out and choose the one I liked.

You can see my own "Straight Key" at the rear to give some idea of the size of the smaller keys. Although initially I liked the look and feel of the key on the left,and it had quite a weighty base it wasn't the one I chose. I found it very difficult to adjust and wasn't too happy with the way that the lead that connects it is on the right hand side of the key rather than at the rear. The little key at the centre was my final choice although I really need to find a base for it now. Note the lever to the right of the key. Moving this closes the contacts so that the key is continuously  "down". I wonder was this designed to help "tuning up" so that you don't have to press the key down?