i have one for my Janome that looks like the first one. the sales lady gave me the wrong one and i tried and tried to get it to pop in place. luckily I took it back and get the right one. it snaps in place over the bobbin area and you move the bar to the size circle you want to make. it has a sharp "tack" the fabric or qlt block goes over. not fond of that but it holds the fabric in place as it goes around.
http://content.janome.com/index.cfm/...ing_Attachment
sorry, very light pic
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