The pictures below show a guide to size of 6mm and 8mm chains,
however the Diamonds are only available for 8mm Chain and in Black or White.
The Diamonds are sold loose so you can space them as close or far apart as you desire.
As a guide, there are 30 links of chain to each metre.
The Diamonds are simple to fit by pushing in from each side of the chain,
once clicked in place they are virtually impossible to remove.
 
 

How to assess the size of 6mm and 8mm Chains The 8mm Chain shown above has links which are approx 2 inches by 1 inch but because they overlap 2 links measure 3 inches.  There are 29 / 30 links to the meter. The 6mm chain shown above has links which are approx 1.5  inches long by .75 inch and because they overlap 2 links measure 2.25 inches. There are 40 links to the meter. .