Electronic vouchers (or eVouchers for short) can be bought for specific treatments or stays and do not represent reservation of a particular time slot.
Once you have purchased an eVoucher, an electronic copy of your order details - including where you'll be going, what treatments you've bought, how much it cost you and the eVoucher validity period - is sent to your email address.
You will need to contact the venue directly to book in before your eVoucher expires (so keep an eye on that date) and must print your order email to take to the venue as proof of purchase.