Pre-War type Crosses of Merit: 2nd class (Silver) and 3rd class (Bronze).

Reverse of pre-war 2nd and 3rd class showing the cut-outs between the arms and rays.
Some early pre-war issues are numbered in the center.  Some exile WW-II crosses made by SPINK will be marked as such near the top.

Pre-war private purchase 1st class cross made by NAGALSKI.  Arms and rays are not separated on this issue.  The image on the right is the marking of the maker on the reverse, A. NAGALSKI, WARSZAWA.

Bronze Cross of Merit with Swords.  This Original example was produced in the workshops of the Second Corps during the Second World War.  It was cast using a sand mould, which gives it a rough appearance.  Spink made examples exhibit higher quality.  The Swords device (especially Swords copied from the Independence Cross) were added to some Pre-War Crosses and were issued during the War, mostly in Poland, to those in the A.K.

 
Typical communist issue of 1st, 2nd and 3rd class awarded between 1952 and 1989.  The arms and rays do not have cut-outs.  Miniatures (in this case with enamel "ribbons") are a nice addition.
 

Recently produced 1st class cross.  There are no cut-outs on this example, but some recently made crosses do have cut-outs similar to the pre-war type.