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to AAPK! Having your grandfathers knives and hatchets is about as good as it gets, congratulations! 
Hope that helps.
Knifeax Detail: Combination knife and ax. Blade and ax interchangeable in same handle. Five-inch Oriental type hunting blade. Length of ax in handle 11 1/4 inches. Length of ax blade 4 1/4 inches. Width of cutting edge on ax 2 1/2 inches. Ax and blade chromium finished. Total weight of ax, knife and handle in compact leather sheath, only 1 pound and 5 ounces, requiring no more space on the person than the ordinary hunting knife. It has met the universal approval of experienced hunters, camper, motorists, scouts and sportsmen. Indestructible pearl handle.
(I thought that was an interesting detail!)
The variations which were produced:
o 261 – Standard Ax – Walnut handle
§ Circa 1935-1957
§ 1964-1967
o 261 Deluxe – Large forged Ax head – Walnut handle
§ 1940-1957
o 561 Deluxe – Large forged Ax head – Genuine Stag handle
§ Circa 1935-1970
o 661 – Standard Ax – Bone Stag handle
§ Circa 1935-1942
o 961 – Standard Ax – Imitation Pearl handle
§ Circa 1935-1957
o 961 Deluxe – Large forged Ax head – Imitation Pearl handle
§ Circa 1935-1957