Smart's Smartalk Unli Call and Text has 3 variation, P25, P50 and P100. The difference is in the validity of the promo subscription where in P25 will only have 1 day of unlimited call and text to Smart/Talk n Text/Red Mobile, while P50 will have 2 days and P100 will have 3 days (this is the most cost effective variant).
Smartalk Unlicall and Text 25
1 day unlimited call and text to Smart/Talk n Text/Red
P25 to register
Just text
UNLI25 to 6406
Smartalk Unlicall and Text 50
2 days unlimited call and text to Smart/Talk n Text/Red
P50 to register
Just text
UNLI50 to 6406
Smartalk Unlicall and Text 100
4 days unlimited call and text to Smart/Talk n Text/Red
P100 to register
Just text
UNLI100 to 6406
This is from Smart Buddy so I supposed that this is only available for prepaid subscribers.
From Smart Buddy