The four objects in the 4 arms of Vishnu are Shankha, Chakra, Gada, Padma or in simplified English equivalents they are Conch, Discus, Mace and lotus.
Now, which arm of Vishnu holds which object? That is an interesting question. The Dwaita philosopher Madhvacharya lists out 24 ways ( i.e. 4X3X2X1) of holding these objects in 4 arms, in his Tantrasara Sangraha. Accordingly, each form (Roopa) holding the objects in a specific way is given a name and worshiped for a specific purpose. These 24 forms (Roopa) are
- Keshava : Shankha, Chakra, Gada, Padma (clockwise starting from the top right hand)
- NarayaNa: Padma, Gada, Chakra, Shankha
- Madhava: Chakra, Shankha, Padma, Gada
- Govinda: Gada, Padma, Shankha, Chakra
- VishNu: Padma, Shankha, Chakra, Gada
- Madhusoodhana: Shankha, Padma, Gada, Chakra
- Trivikrama: Gada, Chakra, Shankha, Padma
- Vaamana: CHakra, Gada, Padma, Shankha
- Shreedhara: Chakra, Gada, Shankha, Padma
- Hrsheekesha: Chakra, Padma, Shankha, Gada
- Padmanaabha: Padma, Chakra, Gada, Shankha
- DaamodaraL Shankha, Gada, Chakra, Padma
- SankarShaNa: Shankha, Padma, Chakra, Gada
- Vaasudeva: Shankha, Chakra, Padma, Gada
- Pradyumna: Shankha, Gada, Padma, Chakra
- Aniruddha: Gada, Shankha, Padma, Chakra
- PuruShottama: Padma, Shankha, Gada, Chakra
- AdhokShaja: Gada, Shankha, Chakra, Padma
- Narasimha: Padma, Gada, Shankha, Chakra
- Achyuta: Padma, Chakra, Shankha, Gada
- Janaardhana: Chakra, Shankha, Gada, Padma
- Upendra: Gada, Chakra, Padma, Shankha
- Hari: Chakra, Padma, Gada, Shankha
- KrShNa: Gada, Padma, Chakra, Shankha
Following image shows the 24 ways in which Udupi Krishna - the Krishna installed by Madhvacharya at Udupi - is decorated to illustrate the 24 forms of Vishnu as explained above.