These are draw bar couplings designed to fit into NEM sockets on British outline OO gauge rolling stock.  he advantage these give is that provide a close connection which will not come uncoupled until a coach is lifted form the track.

Below is an example of Hornby’s British Railways Somerset & Dorset Maunsell coaches coupled on strait track.

The couplings are printed Shapeways’ Black Strong & Flexible material and come in 5 different types:

Type 1 gives 16mm between NEM sockets. (When two type 1’s are used).
Type 2 gives 17mm between NEM sockets. (When two type 2’s are used).
Type 3 gives 18mm between NEM sockets. (When two type 3’s are used).
Type 4 gives 20mm between NEM sockets. (When two type 4’s are used).
Type 5 gives 21.5mm between NEM sockets. (When two type 5’s are used).

And they are available in two pack sizes; 10 couplings and 40 couplings.

A sample pack is also available which has two of each type.

All the couplings are now available in my Shapeways Shop here.