Hello,

Screwfix sell some sleeve anchors and some shield anchors. They look
very similar to me. Is there a difference between them?

SF also sell expansion plugs, which look like a sleeve anchor without
the nut. Is that what they are? Can you use any bolt in them or is
there a rule about the maximum length? I see that the anchors state
the maximum width of the fitting that can be secured.

There are also thru bolts which look like a similar thing. All these
different fixings. Is there a web site that explains them all? My head
aches!