Our e-vouchers here at Climbzone:

A simple gift voucher for an amount of money - Valid for any sessions of the recipients choice, subject to relevant age restrictions. (The amount is shown on the voucher )

OR a places voucher - This voucher can be used to book places on a specific session - either a 1 hour 2 activity session at £19 per person or 1 1/2 hour 3 activity session at £28. The price isn't displayed on the voucher, only the session type it is valid for.