There is a difference:
ASM1300PG2M1103A00 the "A" indicates the accuracy is ±0.05%FS (±0.15 psi). This means that no data point will be off greater than 0.15 psi.
ASM1300PG2M1103B00 the "B" indicates the accuracy is ±0.1% Reading. Results will be better in all pressures < 150 psi
Error @ 0.05%FS Pressure Error at 0.1% Reading
0.15 psi 30 psi 0.03 psi
0.15 psi 100 psi 0.10 psi
0.15 psi 150 psi 0.15 psi
0.15 psi 200 psi 0.20 psi
0.15 psi 300 psi 0.30 psi
Either method will have a Total Error Band < ±0.25% (±0.75 psi)
TEB = % linearity + % hysteresis + % non-repeatability + span & zero settings + thermals