Does anyone use these? I got some when they were on clearance at the grocery store but I am not sure if they are the same as the wilton ones if anyone knows I would appreciate the info. I am wondering because I want to make the baby sweater cake. Two of the tips I have are a 30 and a 24 and I was wondering if they are close to the wilton tips 16 (for zig zag) and 21 (for a shell)

you mean the plastic ones for use with the plunger thingy?
http://acmehardware.com/product_detail.aspx?sku=3420056
i can imagine that the tips might be useable on their own in a bag without a coupler, but in my opinion, a plunger-type mechanism is probably the most useless (and frustrating) decorating tool every invented...well, maybe it's good for dolloping out firm cookie dough, but for piping work it gives you almost no control.