Swapped my tyres back from 30mm CX from the weekend to 35mm touring type for my commute.
But I didn't remember to swap the tubes, or the spares in my seat pack.
28-32mm tubes do not being used in 35mm tyres. 3 blowouts on the way home from work tonight!
I thought the spare tube I put in after the first blowout looked a bit thin.
Never realised 3mm would be so important.