Two squares with the same pair of options, in one band of three boxes but in different rows and boxes. If the band's leftover squares can't take one of the pair, at least one twin is the other number, and a square that sees both twins can't have it.
123456789
123456789
1
3
6
5
5
4
6
7
3
1
45
2
9
6
6
3
24
8
1
7
9
1
4
4
45
8
3
1
3
6
8
1
6
9
6
7
1
The twinsRow 5 in the left boxLoses a pencil mark
The band
A band is three boxes side by side. It holds each number three times, once in each of its rows and once in each of its boxes, which is what makes the count work.
How to spot one
Look for two squares with the same pair that share no row, column or box but sit in one band. Then check the third box's leftover row for the pair.
What it gives you
Removals in the squares that see both twins, usually two or three of them.
Practise Chute remote pairs
Boards that need it, with the owl's hints when you're stuck.