d. The brake unit consists of a braking mechanism housed in a round cast metal case
with a square 1-inch hole in the center. (See Figure 7.)
e. Straps ST-19-A and ST-42 are web straps with a snap hook at each end and a bar
buckle. (See Figure 8.)
f. Four toe clamps are furnished with all models except order numbers 27533-Phil-53
and 27534-Phil-53. (See Figure 9.)
3. Differences between models. Reel units RL-31, RL-31-B, RL-31-C. RL-31-D, and RL-31-
E are identical in most respects. However, some differences do exist.
a. The frames of reel units RL-31-B, RL-31-C, RL-31-D, and RL-31-E are constructed
of sections of pipe reinforced with welded triangular steel plates. (See Figure 10.) Reinforcing
plates are not used on RL-31.
b. The cross braces of RL-31-D and RL-31-E cross over each to form an X. (See