Usually arms on the elbows become worn out faster than on the other parts of the jacket. Earlier patches were sewn on the worn out parts. With their help tweed jacket served much longer. Moreover, the patches could be changed in due course. In the old days it was very important and practical, because according to common decency men should have worn jackets constantly, and the jackets were expensive.
Today elbow patches can be seen on the ready-made jackets with different prices more frequently. Usually they are made of suede or smooth leather. At the same time they are functional and decorative element. Firstly, elbow patches protect elbow area from premature wear and, secondly, they are stylish and can give a jacket a special charm. They look really nice on tweed models in particular.
Though, it is worth bearing in mind that tweed jackets with elbow patches are entirely informal. It’s not a good idea to put them on to important negotiations with conservative partners or to wear them in places, where one should follow an official dress code. However, during the last decades dress codes become softer and softer, and there are more and more occasions to put on a jacket with elbow patches.