The RNLI volunteer lifeboat crew at Tenby are being acknowledged in a special stamp set being produced by the Royal Mail. The charity has not been featured on a UK stamp for more than 20 years. Michael Lewis, Tenby RNLI crew member who is also a postman, delivered a giant stamp to the station on Tuesday - giving the crew a sneak preview of the design which went on sale yesterday (Thursday). The special edition 'Mayday - Rescue at Sea' stamp set features the work of the Royal National Lifeboat Institution at four of the charity's lifeboat stations, as well as the role of HM Coastguard. The new six stamp 'Mayday - Rescue at Sea' issue will run to over 30 million stamps. Four of the set feature RNLI lifeboats: at Tenby (78 pence stamp), Appledore (46p stamp), St. Ives in Cornwall (54p stamp), and Barra in Scotland (1st class stamp). The other two stamps in the collection feature the work of HM Coastguard helicopters from Lee-on- Solent (69p stamp) and Portland (48p stamp). Freddy Broomhead, RNLI lifeboat operations manager at Tenby, said the crew were delighted that the station's Tamar lifeboat was to feature on one of the stamps. He said: "Being chosen from the 233 RNLI lifeboat stations across the UK and Ireland to be one of the four stamps is a real honour for the RNLI at Tenby. It has been an exciting period for Tenby, with the delivery of the first Tamar class lifeboat in the RNLI and the construction of a purpose-built boathouse; the stamps immortalise these exciting developments and secure Tenby's RNLI's place on the map. "The station's inshore and all-weather RNLI lifeboats launched 49 times last year, making Tenby the fifth busiest RNLI lifeboat station in Wales. The stamp will be a constant reminder of the bravery of RNLI volunteers who are on call 24/7 to save lives at sea." Huw Roberts, director of Welsh Affairs, Royal Mail Group, said: "The 'Mayday - Rescue at Sea' stamps are a special tribute to the life-saving organisations like the RNLI that will be seen by countless people on letters and parcels around the world. We hope the stamps will remind us all of their immense courage and bravery." The RNLI, with the help of Buckingham Covers - a specialist producer of first day covers - has created a unique set of first day covers featuring the Royal Mail 'Mayday - Rescue at Sea' stamps. There will also be a limited edition special stamp sheet featuring 10 RNLI lifeboats and a lifeguard rescue watercraft, from around the coast of the UK. The RNLI aims to raise up to £20,000 for the proposed RNLI Memorial Garden at the charity's headquarters in Poole. 2008 is also the centenary of the adoption of the SOS distress signal, and to mark this anniversary, Royal Mail has worked with Walsall Security Printers to re-create the famous sequence of 'dots' and 'dashes' along the top and bottom edges of the stamps.