I've compared the 3453 (which is the new one) to the 2853 & 2953, in hand at stores.
If you hold them up next to each other, head to head, the 3453 is almost 1/2 longer in over all length (front to back). Diameter or side to side the 3453 is smaller thou. It's odd to me they made the 3453 longer in the head, then it's big brother. Yeah the M18 is a bigger tool in girth, but it's shorter in the head length wise.
Sometimes putting in backing (that carpenters forgot) having a 1/2" shorter tool makes a difference. The head size AKA length, squeezing in a tight space, is where it's at for me & my needs.
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