Comparison : Item # MR1, 4 1/2 x 5 1/2" Invoice Envelope
Item # MR2, 4 1/2 x 5 1/2" Invoice Envelope
Item # MR3, 4 1/2 x 5 1/2" Invoice Envelope
Item # MR4, 4 1/2 x 5 1/2" Invoice Envelope
Item # MR24, 4 1/2 x 5 1/2" Invoice Envelope