Below is a copy of how I determine the different types of openers

Click on the TYPE A etc to view the picture.

Type A  has incised or stamped letters.



Type B  has incised or stamped letters but has added point to either side of the head of the opener

Type C  has raised writing but in a recessed panel, & no numbers on head.

Type C2 has raised writing and no panel.

Type D  has raised writing but in a recessed panel and has an added point to either side of head.

Type D2  has raised writing but has an added point to either side of the head.

Type E   has has raised writing in a recessed panel but has the
numbers RD. 702661 on either side of the head.

Type F   has raised writing but in a recessed panel but has the
numbers RD. 702661 on either side of then head and also has an added point on either side of the head.

Type G  has raised writing but in a recessed panel and a crown shaped head
eight the numbers RD 811274 on one side and PT. 466444 on the other.

Type H  has raised writing but in a recessed panel and has a very broad head with the numbers RD. 708483 on either side of the head.

Type I has raised writing but in a recessed panel has a VERY broad head, this type comes with and without numbers on the head.

Type J  this opener is a stopper and combination crown seal opener.

There is also many variations for the different types that I have listed above.