005 Discovery Set
General Information
The following information has been collected from original newspapers, catalogs, and magazines, some of which are freely available for reference below. The rest can be found in the site’s gallery. No aggregate catalogs (BrickLink, Brickset, etc.) were used.
Instructions:
Always included a 001 Gears instruction manual.
For late 1966 through early 1967, 005's came with an Imaginations Inc. Order Catalog (this has no form number, you can find it here). This catalog was only included with mail offer 005s from that period.
Advertised Part Count(s): 328 pieces
005 Trial Offer Brochure 1970 FAO Schwarz Catalog
First Year Confirmed Available: 1965 (USA)
I've written extensively why I'm confident about this date and designated it as confirmed here.
USA only.
Most Likely Retirement Date: 1970 (USA)
The set appears in newspapers from late 1971 at a select few retailers, but all carry 40%+ discounts. It makes its final appearance in catalogs in 1970.
Last Year Seen Available: 1971
Tri City Herald, October 13th, 1971
Aliases: Discovery Set
Suggested Retail Price(s): $9.95 - $12.00 (USA)
Known Discounted Price(s): $6.77
Rarity Score (Index): 3/7
Known Box/Packing Variants
The 005 Discovery Set's outer box has no known variants, oddly so. It is uniquely exempt from the 1967 update which replaced suggested age ranges with "FOR ALL AGES", likely because the 005 was the only 1965 set to never have included an age range in the first place.
Weirdly, however, it was also exempt from the update that changed boxes to have eight patents instead of two. I'm also not aware of any 005 with the 1970 "Some parts are made in Denmark" sticker. This is uniquely the only set exempt from all of these.
1969+ copies will have a single piece plastic gray tray for the 285's tray.
Box/Overview
The 005 Discovery Set was first released in 1965 as a mail away trial offer set. Different than 1963's Special Introductory Set, it was a no obligation examination during the trial period (10 days) before payment was expected.
Managed through Imaginations Inc, the offer was meant to introduce LEGO to families who hadn't owned any. Hence the set's name "Discovery":
The only unique feature of the box is the lack of an age range entirely.
Also, I'm almost positive the next side features a model intended to be a tank (which was supposedly a big no-no back then for LEGO). I'm almost positive these images were taken from LEGO's own photography department:
The back of the box shows models and images that are also used in the 005's brochure:

It should also be noted the set continued production after the 1965-67 offer ended, reaching regular retail in late 1967. If you want to learn more about the 005's distribution, I explore such in this article: Finding the 005 Discovery Set's Release Date.
To give an abridged version, it was distributed through Imaginations Inc. from 1965-67. Starting in 1967, it appears at a wide variety of stores including Bon Marche, FAO Schwarz, Gregg's, Marshall Fields, and Polsky's. There are 10+ more, you can find them in the site gallery, just search "005" and check the retailer tags returned. The reason I clarify the retailers specifically is because historically, the set has been assumed to be an FAO exclusive as no other appearances in media, nor its Imaginations Inc distribution, were known.
There are no known differences between the Imaginations Inc version and the retail box. As the set was designed with mail order in mind, it never had a shipping box alternate as is seen with 1966-1970 Sears/JCPenney catalog sets. Instead, it shipped with an outer box protecting its colorful box:

The above example is postmarked for March 1966. You can read more about the 005 Discovery set in its dedicated investigative article in which I delve deep into all the evidence I've gathered.
Contents
The set was composed of two sets that were also new for 1965: the 001 Gears and the 285 Basic Set.
As such, there should be no surprises:
The example above includes an inspection slip. It was found with the set when it was originally purchased, but may have (and would make more sense to have) come with the mailer box 002 that it was bundled with.
When ordered from Imaginations Inc in the late 1966 wave, the 005 also included an exclusive idea book. Here is one page:

If one were to order sets from this catalog, they came in their own mailer box instead of the colorful box (aside from the 005). The only one that has not yet been found is the 042 Pull Toy's box.
Historical Examples
We go over the 005 Discovery set's prototype box extensively in the dedicated article linked above. Here, we will largely cover the same observations.
The 005's prototype box was used to assemble the original 1965 brochure promoting the set. This one was produced for the 1966 season, but it's mostly the same idea as the 1965 version, just much larger:

The most prominent detail is the unique formatting for the set's number and name, while the finalized set uses the same format as the 003 and 004 sets.
Also similar to the prototypes for the 003 and 004 sets, as well as the 615 set, 005's prototype is missing the box tabs. This detail was very important in dating the 005 set definitively to 1965.
Another vital clue was the formatting of the patents, which is in the 1961-1964 format where the patents are under every LEGO logo:

It also appears the set number is absent from its final place on the side of the box.
Given the patents are only present in one place on the finalized box, it is possible the others were decidedly replaced to instead include the set number and the age range. The 005 set was not required to account for either of these, but its likely the formatting for the patents was consistently applied to all sets in 1965 to avoid unneeded complexity.
It's also important to note the brochure omits Samsonite's name entirely. As my pamphlet is a later version from 1966, long after Samsonite's 1965 rebrand, it's possible the choice was deliberate for this ad, so as to not hint at Samsonite's involvement. We see similar obfuscation with all 1965+ sets, where Samsonite's name is reduced to fine print. I've seen it work that way in practice, as I'd missed the 1965 wave at first because Samsonite's name is missing from most adverts.