The Cadair Idris range of envelopes is the premium range of secure, easy to close, peel & seal envelopes for communications that you don't want to have that 'commercial' feel, as with no opaque they will ensure that your letter really stands out. These are used a lot by high-end brands to promote their products but are also ideal for invitations, but saves you having to wet the flap to close. Available in a range of matching sizes.ing sizes.