Payroll Giving is voluntary scheme where you as an individual can make a donation to your chosen 'donee organisation' (The Spirit of Adventure Trust) directly from your pay.
The scheme is administered by the IRD via the PAYE system. Employers can sign up for the scheme and make it available to their staff, you can then have the value of the donation you decide on automatically deducted from your pay and sent directly to the Spirit.
You in turn receive a Tax Credit at the time of each donation, so there is no need to collect donation receipts, you have already received your tax credit.
For more detailed information see:
The Charities website link on Payroll Giving
The Payroll Giving Guide released by the Inland Revenue
Payroll Giving for individuals - IRD website link