Original Sperzel Trim-lok machine heads 3 & 3
Sperzel tuning keys offer a unique design and precise machining tolerances to eliminate shaft wobble and provide minimum backlash and endplay, which greatly reduce your guitar's tuning problems. Sperzel's housing extends further up the shaft with the bushing threads on the outside, keeping the string post solid.
All Trim-Lok models are easily reversible, allowing conversion to left-handed or custom configurations. Sperzel has been manufacturing staggered string posts since the late 1970s. Guitars with tilt-back head stocks use all one post height.
Quick, simple, reliable re-stringing
The locking feature eliminates the need for multiple string wraps, and trem users no longer need a locking nut that deadens string sustain and all annoying Allen screws and wrenches (added weight). Tired of tying strings? This is the answer. This model is proven to hold strings tightly, allowing the guitar to stay in tune to improve playing enjoyment. The Trim-Lok is a mechanical type locking system that can be used on ANY guitar, including non-trem or acoustic.
Simply insert your string into the hole and pull all the way through the post until tight, while holding string screw locking knob in until string is locked to post. Do not over-tighten; finger tight will do. Then, tune to pitch (Approximately 1/2 turn with tuning button). You should be in tune; cut excess string and repeat the process for remaining strings