Security components presenting significant difficulties (8)

'security components' is the definition.
The definition and answer can be both man-made objects as well as being plural nouns.
Perhaps there's an association between them I don't understand?

'significant difficulties' is the wordplay.
'significant' becomes 'key' (I've seen this in another clue).
'difficulties' becomes 'holes' (hole is a kind of difficulty).
'key'+'holes'='KEYHOLES'

'presenting' acts as a link.

Can you help me to learn more?