Abstract: A pistol-shaped automatically retracting chalk-line dispenser comprises a three-member housing enclosing two separate chambers. The upper, chalk-receiving chamber, contains a double-walled chalk-line spool and a line-guiding roller. A seal on the chalk-line spool shaft prevents chalk dust from entering the second chamber, which contains drive gears, the line-retracting spring, and a trigger-actuated latching brake mechanism. In one embodiment, a finger-like projection from the trigger is initially brought to bear on a rotating cap to brake the rate of line retraction as the trigger is pulled rearwardly. If the trigger is pulled back more than a predetermined distance, the finger-like projection snaps into engagement between the teeth of a sprocket attached to the cap and thus locks the retraction mechanism.

Abstract: A knee support apparatus for use as a flotation raft for utilizing a flotation raft with each foot for permitting ease of support of an individual upon a surface, such as concrete to be finished. Each raft includes a knee engaging loop, and a rearwardly oriented foot receiving socket. A modification of the invention includes padding for enhancing comfort of the individual upon an uncured concrete surface.