Spring-assisted knives
The name spring-assisted or assisted-opening does not explain every part of a knife's construction. Before choosing a model, check the stated mechanism, activation method, lock and direction of blade travel. These details affect handling and storage, so appearance alone is not enough to identify them.
One example in this category is the United Cutlery USMC Colossal Blackout Stiletto. It measures 28.8 cm overall, with a 13.2 cm blade and a closed length of 15.9 cm. Listed blade thickness is 2.5 mm, blade width is 1.7 cm and weight is 140 g. These figures describe this particular model, not every knife with a similar profile.
Points to compare
Match the closed length to a secure storage location. Check the weight, handle shape, exact blade material and the locking action described by the maker. If the mechanism or its operation is unclear, use the instructions for that product rather than assuming it works like another design.
Store the knife closed and protected against accidental activation, away from children. Inspect the mechanism, lock and handle attachment regularly. Match cleaning and maintenance to the stated steel and finish, and do not dismantle the mechanism in a way the maker does not provide for.