They are a few mm's thicker, nothing massive but definitely different than the original tongues I had in my FT4 Pro's (which were the standard ones). I bought them to reduce volume slightly and I guess they did the trick, the skates felt more snug all around which was a plus for me... I did notice the laces are slightly shorter now so it did add a little volume or size across the laces if that means anything. As far as the tongue, it's comfortable but needs a little breaking in, the extra D3O on the upper half felt like it could shape/contour a bit more with use but all in all I'm happy with mine after one use.