No. 42 & 44
Enrique Wiese started the production of MBs in Spain, post WWII. It is speculated that domestic production was taken up at that time because the Hamburg factory could not meet local and international demand after its bombing in 1944. Also, trade controls mandated by the Spanish dictatorship made it difficult to import pens at that time. Labour and parts were cheaper in Spain, and so MBs would only be affordable in the country if produced there. This makes sense because it seems that Spain's production of MBs stopped once injection moulding technology was introduced in the late 50s and through the 60s. The new technology reduced the need for manual labour considerably and with it the cost of pens too. One series produced in Spain resembled the design of the 34x of the 1950s. They were numbered as 4x and came in four colours - grey stripe, brown stripe, green stripe, and black. These pens have a special imprint on one side of the cap 'Fabricado en Espana por E. Wiese' or Made in Spain for E. Weise. I have two 44s and had a 42 in my collection.
The 44 in grey striped colour is a middle-sized pen from the 4x series, slightly larger than the 42. Both are piston fillers, as opposed to the 2x series which were identical looking but button fillers. The single brass cap ring and poor quality plating on the clip are quite weathered and show the modest quality of materials used to make these pens. I really do appreciate the long ink window that is visible even when the cap is on. The colour of these pens is truly beautiful - bright and deep. Also, they have aged very well - there is no visible oxidization like one sees so commonly on the grey or green striped 14x Meisterstuck which cost several times more than the humble Spanish pens.
A few months after I purchased the 42, I discovered a crack in it and exchanged it for a 44 in golden brown. So now, as you can see in the pic on the right, I have two 44s in different colours. The green stripe colour is missing and might find a home in my collection some day.
Guillen, J. M. (2014). Montblanc Pens Made in Spain. Guillen.