The 1908-09 stamps were issued in imperforate form for private coil makers. These coil manufacturers joined the sheets, then cut them into strips, which were themselves joined to form very long coils. The 2¢ Washington was issued in 400 subject sheets, then divided into sheets of 100. Fifteen of these sheets were pasted together, and then cut into coils of 3,000 stamps each. Every twentieth stamp on the coils was pasted together.Long coils worked extremely well in the newly developed coil machines of the day. Please see photos and ask questions prior to purchasing.