In answer to some of the threads posted about air refills for air guns in Colchester. We ( Essex School of Diving Ltd) are now able to fill your air bottles to 300 bar. We only fill direct to the tank via a 300 bar DIN connection. All tanks must be in date. We are not a shop so are not restricted to shop hours. If you would like a refill, please contact us on 07760 665094 after 10.00am. We are situated just half a mile from North Station Colchester.