Have you added something extra to your Sonic, post purchase or are you just feeling extra generous? Please make sure you confirm in the dialog box why you wish to send us this payment. 

'Joe Blogg's Custom Sonic - Extra Emitter Top'

'I just wanted to help! I hope this helps!'
 
Please see the drop down list to choose the amount. If you require to pay / or wish to donate an amount not shown, please add two to your basket - 

Example - 
 
You wish to pay £45 - select £40 and add to your basket then add a further £5.