As it says really! I have an almost 4 month old and a 22 month old and would like an easy-on easy-off sling to use for my youngest when it's too much of a faff to tie the Moby on (e.g. for popping into the garden to hang the washing out).
Doesn't need to be as comfy or adaptable as the Moby as it will only be used for my youngest and only for short periods. I have been considering a ring sling but am very used to having both hands 'free' and am not sure how feasible that would be with a 4 month old. I have also looked at the connecta baby carrier which seems pretty easy to get on/off.