The unclued lights (one of two words) are of a kind.
 

Across

 
1    Confines at convenience stores (5)
4    Prison visitor, not in Rolls Royce, sadly places eggs for fertilization (9)
11    Over half the train to Dover isn’t broad-gauge (6)
14    Range of school note (5)
15    I left seafood dish for old highwayman (5)
16    German philosopher and literary critic who tends the flock (6)
22    Decide against having completed the crossword, we hear (8)
23    Italian number silly fellows adopted (7)
24    Engagements of heartless Man Utd player (4)
25    Dull Eisteddfod champion returns (4)
27    Dire Straits for Bolshevik opponent (7)
29    One male with handy phone won’t move...