1/2 Extension Progression

1/2" Drive SG12 1927

All S-12s except the 4th that is a SX-12. 

top photo 1927 and 1928 square shafts 

2nd extension 1930s until 1935/6. 

3rd style started 1937 to 1946/7. 

4th head style post 1948 

These are all S-12s except the 4th that is a SX-12. On the top photo I have two examples date marked 1927 and 1928. The only period where square shafts are used are from this period 1920s until 1930 or so. The 2nd extension is from the 1930s until 1935/6. These have blank heads and the lable is on the shaft. The Logo is large with a larger S and the up turned dash. The 3rd from the top this style started is 1937 and lasted until 1946/7. These have the knurled head seen is many WWII period tools. The 4th extension has a head style from 1948 and lasted past 1970. 

Number

Description

Date 

No 37F

Extension – Short

1927 – 1928

S-2

Extension (2 inch)

1931-1948

S-3

Extension (3.5 inch)

1941-1948

S-6

Extension (5 inch)

1925-1948

S-12

Extension (10 inch)

1925 -1948

S-20

Extension (20 inch?)

1927-1948

S-24

Extension (24 inch?)

1937-1948

S-30

Extension (30 inch)

1941-1948

S-36

Extension (36 inch)

1948

 

Number

Description

Date 

SX-2

Extension 2”

1950-1978

SX-3

Extension 3 ½”

1950-1978

SX-5

Extension  5”

1950-1978

SX-10

Extension  10”

1950-1978

SX-15

Extension 15”

1978

SX-20

Extension  20”

1950-1978

SX-24

Extension  24”

1953-1978

SX-30

Extension  30”

1950 – 1953

SX-36

Extension  36

1950-1978

1/2 SG series

1/2" Drive SG-6

SG-6 ? Unmarked

I am not 100% sure of this one. It appears to be Snap-on but there is no logo on this tool. There is are stamped numbers 41-B-311-290. There are 2 variants a 6 inch and 12 inch. 

Number

Description

Date 

SG-6

Extension (6 inch W/ grip)

1925 – 1937

SG-12

Extension (12 inch grip)

1925 – 1937