With the onset of autumn coming (OK were not out of August) I thought I'd see if my rather old BLT's still worked.... They are an early model, halogen front and standard rear filament arrangement - both using the same type of casing, and a bottle battery. The units are at least 12 years old, and I paid about £80 for them at the time. Well, they fired up, all be it dimly (not been used for years as I've only recently started commuting again). £6.99 down at Maplin for a 6v 4.5 ah battery (old one was 2.8ah) and only just crammed it in the bottle (now square in the middle) - rewired and all working. Will probably upgrade the front halogen to a brighter one - and maybe use the old front bulb in the rear. These will be used along with a Smart 1/2w rear led, rear helmet led, and my existing cateye opticube front. Pleased as punch ! These old lights are well tough.