It's the amount I have prepaid to my Dynadot account! You can use all the $505 to buy domains from dynadot.com with bulk Bulk Pricing.
Bulk Pricing: com $7.50 net $5.75 org $4.99 * info $1.99 * biz $7.50 mobi $8.99 ** ws $6.99 us $6.99 cn $1.99 *** co.uk $7.99 **** cc $27.99 tv $32.99 eu $8.99