A London non-league football club’s away kit has become a surprise hit in Spain, because of the anti-fascist message embroidered into it. Clapton Community FC have taken more than 5,400 pre-orders for their shirts, after pictures of the kit gained media attention on the continent.

The red, purple and yellow shirt was worn for the first time last Saturday, and the colour scheme is inspired by the flag of the Second Spanish Republic, and honours the International Brigades who fought in the civil war. The back of the shirt features the slogan “no pasarán”, meaning “they shall not pass”, which was used by anti-fascist fighters in the 1930s. It also features the three-pointed star of the International Brigades, and was released to commemorate the 80th anniversary of the end of the conflict.

Facebook Twitter Pinterest The Clapton CFC kit was announced in June, but the club did not anticipate what a success it would be. Photograph: Clapton CFC

The shirt design was chosen after members voted from a selection of 16 kits, and the designer, writing on the Clapton CFC website, said: “I really wanted to make something that marked the importance of the sacrifice of those who fought against fascism.”

The club said they only expected to sell about 250 shirts this season. The kit is manufactured by the Italian firm Rage Sports, chosen specifically by the club because it is a small, ethical manufacturer that sources its materials from companies that agree to pay workers fairly. Rage Sports produces kits for grassroots football clubs that are specifically involved in fighting racism, fascism and inequality.

Facebook Twitter Pinterest The Spanish civil war anti-fascist slogan on the Clapton CFC shirt. Photograph: Clapton CFC

Maurizio Affuso, who works for Rage, is quoted on the club’s website as saying: “Rage Sport will always be there for the Clapton fans because like them we believe in a new way of doing football and because we strongly believe some battles can be fought both on and off the pitch.”

The unprecedented interest is not without its drawbacks. Volunteers have been working all week to handle orders and respond to a multitude of messages sent to the club via social media and email, and on Thursday the team announced they had paused new orders for the shirt “while we and our supplier catch up with the sudden huge number of orders”.

Sports quiz of the week: 30 WhatsApp groups, 4,000 shirts and 98,000 calories Read more

The national secretary of the International Brigade Memorial Trust, Jim Jump, said: “We’re delighted that the shirt highlights the sacrifice made by those who joined the International Brigades, and we are excited that some of the income from the shirts will enable us to work with Clapton CFC on education and memorial initiatives here in the UK.”

The club said they would use some of the money to help with running costs, but were earmarking funds to be donated to the memorial trust, which helps to preserve the memory of those who travelled to Spain to fight in the war.

Facebook Twitter Pinterest A Spanish civil war propaganda poster. Photograph: handout/Spanish Civil War exhibition

Clapton CFC have only existed since February, when they were set up in response to a dispute between fans and owners of Clapton FC.

The Clapton Ultras – as their enthusiastic and political supporters had come to be known – boycotted home games at the club’s historic Old Spotted Dog Ground for the whole of the 2017-18 season, after the chief executive attempted to liquidate the charity running the club, who had been playing at the ground since 1888.

Why would anyone be a Sunday league referee? The love of the game Read more

Clapton CFC will compete in the Middlesex Counties football league, and are temporarily based in Walthamstow, east London. They said they hoped to fulfil all the shirt orders within two months, and asked purchasers to “please be patient with us because no one could have expected this level of demand”.

The designer, Thom, added on the website: “We have always been known as fans who do not accept racism, sexism and homophobia, so it made total sense. We didn’t expect our tiny club to be noticed by Spanish football fans but we’re delighted nonetheless.”