The misprint shown below is commonly called an attached tab or a butterfly error. The silver certificate below is a very minor misprint that would sell for around $50. Severe butterfly misprints can be much more severe. The attached tab can get as big as three or four inches. The value of any butterfly or attached tab misprint is based on the severity of the error and the condition of the actual bill.
Please send us an image of your misprint so we can make an offer. firstname.lastname@example.org