[perezfan]

Likely early to late 1960s. It was on my watch list forever, as I like the look more than the current Yankee Cap (with the larger/bolder "NY").

Seller was aggressive on his price, so I never actively pursued it. You can go to Baseball Almanac, and easily research who wore #40 between the years of 1960 - '68. That is the time-frame I would estimate for this Cap, based on style/tagging/etc.

Some additional background for you...

Tim McAuliffe, Leslie, KM Pro and Pro McAuliffe

Tim McAuliffe, founded in 1896, was a distributor of sports equipment, jerseys and caps. Jerseys were made under private label by Stall and Dean. McAuliffe caps were manufactured mainly by the Leslie Company, although during the latter 1950’s and the 1960’s New Era also made caps for McAuliffe. The Leslie Company was owned by Jack Kaufman. The KM Pro stamp on the sweatband almost certainly stands for Kaufman-McAuliffe. In the 1940's and early 1950's, KM Pro caps were distributed by Mitchell & Ness, but by the mid 1950’s all KM Pro caps were sold under the McAuliffe label. McAuliffe caps, along with Wilson, were the dominant brands used by MLB teams from the mid 1950's to late 1960's; as of 1972 all 24 MLB teams had used McAuliffe or KM Pro caps at some point. But by the late 1960’s Wilson and New Era had captured significant MLB cap business, so McAuliffe decided to focus exclusively on jerseys and equipment. The McAuliffe label disappeared from caps during 1969. The Leslie Company continued manufacturing caps into the 1970’s; pro caps had KM Pro tags, retail caps had Leslie tags, though you could buy a KM Pro cap if you wrote to the company. But with New Era increasingly dominating the market, KM Pro ceased operations after the 1976 season

Nice pickup!