Yip. caustic soda. Make sure you're in a well ventilated room, it'll knock you bandy...
Don't leave them in too long, don't do too strong a mixture, my mate dissolved a pair of DX once.... Start with a weak mixture and if it doesn't touch your anno, start adding the caustic. keep a close eye on them. Rinse in plenty of water and don't get it on your skin.
Have fun!!!