This funny engineer tumbler features the quote "Engineer By Day. Ninja By Night." on a black vacuum-insulated stainless steel body — available in 20oz ($34.95) or 30oz ($39.95), with a powder coat finish built for daily use on the job site, in the office, or anywhere in between. A specific, practical gift for any engineer who operates at a level most people don't see.
Engineers solve problems that other people don't know exist. This tumbler acknowledges that duality — the professional precision they bring to every project, and the behind-the-scenes competence that doesn't make it onto any org chart. The vacuum insulation keeps hot drinks hot and cold drinks cold, the stainless steel construction handles the demands of a full workday, and the quote does the rest.
"Engineer By Day. Ninja By Night."
Tumbler Specs and Construction
The tumbler is built from stainless steel with a powder coat finish in black — durable, grip-friendly, and resistant to scratches under normal daily use. The double-wall vacuum insulation keeps beverages at temperature for extended periods, making it practical for long site visits, commutes, or desk use. Hand wash only for best results to preserve both the insulation performance and the printed design.
- Sizes: 20oz ($34.95) or 30oz ($39.95) — same quote and construction, more capacity
- Material: Stainless steel with powder coat finish — Black
- Insulation: Double-wall vacuum — keeps hot drinks hot, cold drinks cold
- Print: "Engineer By Day. Ninja By Night." on one side
- Care: Hand wash recommended for best results
Choosing Your Size
The 20oz is the right call for engineers who prefer a standard travel tumbler size — easy to carry, fits most cup holders, and handles a full morning's worth of coffee. The 30oz suits anyone who works long shifts, prefers not to refill, or drinks slowly and wants the temperature to hold throughout the day. Both sizes display the same quote and use identical stainless steel vacuum construction.
Who This Gift Is For
This tumbler was made for the engineer who puts in the hours and rarely gets acknowledged for it. It works for mechanical engineers, civil engineers, electrical engineers, software engineers, aerospace engineers, and any professional who carries the title. The quote is profession-specific rather than generic, which is what makes it a gift worth giving — and worth keeping.
Ideal gifting occasions include:
- Birthdays and work anniversaries at any career stage
- Graduation gifts for new engineers entering the field
- Mother's Day and Father's Day for engineer parents
- Christmas and holiday gift exchanges
- Appreciation gifts from a team, manager, or collaborator
- Just-because gifts that actually name what the recipient does
A Tumbler That Earns Its Place on the Desk
Generic tumblers get forgotten in the cabinet. This one earns a permanent spot because the quote is specific enough to feel personal and the vacuum insulation is practical enough to reach for every morning. The powder coat finish keeps it looking sharp through the demands of a full workday, and the black colorway works equally well in the office or on the job site.
Browse the full tumblers for engineers collection for additional styles, or explore all gifts for engineers to build a complete gift set. For a coordinated holiday gift, the ornaments for engineers collection pairs well with this tumbler.
What sizes does this tumbler come in?
The engineer tumbler is available in 20oz at $34.95 and 30oz at $39.95. Both feature the same "Engineer By Day. Ninja By Night." quote on a black stainless steel body with vacuum insulation and powder coat finish. The 20oz is a standard travel size. The 30oz is better for longer shifts or anyone who prefers not to refill mid-day.
Does this tumbler keep drinks hot and cold?
Yes — the tumbler uses double-wall vacuum insulation to keep hot drinks hot and cold drinks cold for extended periods. This makes it practical for long commutes, job site visits, or full-day desk use where reheating or refilling isn't always convenient. Both the 20oz and 30oz sizes use the same insulation construction.
What is the tumbler made from?
The tumbler is made from stainless steel with a powder coat finish in black. The stainless steel body provides durability for daily use, and the powder coat finish is grip-friendly and scratch-resistant under normal conditions. The double-wall vacuum construction sits between the inner and outer stainless steel walls.
Is the tumbler dishwasher safe?
Hand wash is recommended for best results. Dishwashers can degrade the vacuum insulation performance and wear down the printed design over time. Washing by hand with warm water and mild soap preserves both the tumbler's temperature retention and the "Engineer By Day. Ninja By Night." print for long-term daily use.
What types of engineers is this tumbler for?
The tumbler suits any professional who carries the engineer title — mechanical engineers, civil engineers, electrical engineers, software engineers, aerospace engineers, and beyond. The quote "Engineer By Day. Ninja By Night." speaks to the profession itself rather than a specific engineering discipline, making it a versatile gift across all fields.
What quote is on the tumbler?
The tumbler features the quote "Engineer By Day. Ninja By Night." printed on one side of the black stainless steel body. It is occupation-specific rather than a generic motivational phrase — acknowledging both the engineer's professional identity and the behind-the-scenes competence that defines the role.
Which size should I choose — 20oz or 30oz?
Choose the 20oz if the recipient prefers a standard travel tumbler that fits most cup holders and handles a typical morning of coffee. Choose the 30oz if they work long shifts, drink slowly throughout the day, or prefer not to refill. Both sizes feature the same quote, construction, and vacuum insulation — the only difference is capacity.